There are many here wiser than I am but prefer Southwest first (for the low $) then Alaska (for the direct flights to Hawaii and Florida). Because Alaska is partnered with British Airways and American as long as there is a saver fare on AS (usually 12.5 k miles one way) I can book using BA avios or American miles. American has a very easy to use website to find award availability, in fact I find it easier to use than Alaska's. British Airways website is stupid and dumb BUT because they are distance based you can score a flight for potentially less miles than the standard 12.5k, and even though their website is painful calling in to book is really fun because they have British accents.
BA is also nice because you can immediately transfer over URs' to them. In the case where I am booking with Avios I search on Americans site to find Saver fares (usually on Alaska metal) then call them up with the flight info. You can also use a site like awardhacker.com and it will bring up the cost of in miles of a flight over various airlines.
Basically, if it were me, I would go with the airline that is easiest to acquire the most miles. That pretty much means American--I just got myself and my DH approved for the Aviator business which will give 50k after the first purchase (af $95, not waived). I posted about it yesterday but for each of us doing that we will pay 190$ for 100k American miles which will get us 4 round trip tickets worth (at the very least) $1500 in direct flights to Orlando on Alaska.
As for your question about not seeing the fare on American that you can see on Alaska, well I am not sure on that one. I haven't run into it before. My first assumption is that it wouldn't be bookable but I am not sure and hopefully someone else can figure it out. Also--If your miles expire from Alaska maybe try giving them a call? My DH's expired and they offered me a one time courtesy reinstatement. I am considering trying my luck with the American miles I just let expire for him but based on my research I don't think I will be so lucky there.
ETA: I noticed you wanted to fly first so ignore my #'s---I am a economy girl. In fact maybe ignore all of it. Not sure what applies once you get into the fancy world of first class
Wow, thanks, so much info. From what I read everything seems to work the same for first as economy... just need more points!
Since this is supposed to be "nice" trip, and it's only for one way, figured it might be a good time to be comfortable on a longer flight. That's always the worst part of the end of vaca, that flight back brings you back to reality real quick. Hubby's never had a taste of first so since it's points, might as well splurge if we can and extend that vaca feeling a bit.
Seems like AS is distance based too, which is why it needs 30k at least for ANC to PHL. And that's the lowest for first, as a non refundable. It's goes up to like 60-70k one way
If that's my only options we're moving to the back of the plane, hehe.
Google flights is awesome for figuring out what airlines you may be looking at for a given route and if that is what you are doing then you are on the right track. The price is only a consideration if you plan to pay using points. If you are booking an award flight, the cash price doesn't matter. The airline's award chart does. Award hacker will also give you an idea.
http://www.awardhacker.com
Now, to your questions: AA is a One World alliance and therefore a transfer partner of all other One World Alliance airlines. AS does not belong to an alliance but does have a good number of transfer partners, including AA. You mention you have transfer partners for both but I'm not sure what you are trying to convey here. Does that mean you have miles with a partner airline of both AA and AS, like maybe BA? If so, keep in mind BA has a distance based award chart and may cost you more BA Avios than a different partner with a different award chart.
It is easier to accumulate AA miles than AS miles. AS has 2 credit cards, 1 biz, 1 personal by BOA. The standard bonus offer is only 30K miles. SPG is the only other points currency that transfers directly to AS. AA has more credit cards with a higher bonus offer than AS. Barclay and Citi both personal and biz with 50k and up bonus offers. I took a look at your flights and I do see saver business/first on AA but that is 30K miles each way so you need 60K per person. I didn't see anything on AS that was less than 60K each way in first. I only saw main cabin awards for 25K and 30K. So whatever flight you found may not be available at that same award cost when you are ready. Do keep that in mind.
Second question: That generally refers to finding award availability on a partner airline that you don;t intend to book with because the airline miles you are using won;t show the partner space your are looking for. Booking Cathay Pacific with AA miles would be an example. AA does not ever show Cathay Pacific on their website for award booking. I have to look for the Cathay Pacific award flight on BA or Quantas. Then, once I find it, I can call AA and book that flight using my AA miles. Keep in mind sometimes partner airlines will show phantom award space. You see it there but it doesn't really exist.
Making the choice between using airline miles or using UR, MR points to book a flight comes down to a number of factors for me. Which one will cost me less in points, how much do I value said points and how easy are they to accumulate and do I have other more important plans for those points at the moment. I will use our flights to Antarctica as an example. When we initially booked our flights, they were 690,000 or so for the two of us total. Right now, the same flights are $7,953 per person so $15,906. I would need 1,060,400 UR points to book that. So AA miles is a clear winner. But even if the miles and UR points were the same, I'd likely use the AA miles because I value them less than UR.
Ah, sorry about the transfer partner confusion. I have MR, SPG, and UR points in the budget to use for this, but no direct airline points. We don't fly much outside of SW for personal. The points I had been earning from business trips I managed to let expire on AA (which I still kick myself for, IIRC I had about 12k go poof after diligently keeping them active for several years), I still have a couple thousand in BA Avios and the same in United. But no where close to actually being able to redeem them for anything
I think hubby has nothing because I forgot to try to save the little bit he had in AA and before that I'm not even sure he opened a FF account from his UK trips for work (he does kill me sometimes) but if he did those were forgotten and expired too. So I think I have points that can transfer to either airline, either directly or roundabout. And I'm not married to AS or AA but they were easy to start with.
We only need a one way for the flight. We're doing a one-way cruise to Alaska so I'm looking for the flight home, which is why we can splurge a bit for First if I can find the right award. As a random date I picked 5/3/2019 - it's also shoulder season like we'll be in for our cruise in Sep 2019 - just to get a feel for how many routes are available (and comparing to the routes available in 9/18) and rough ideas for points. On that date AS has an option for AS106 > AA2113 for 25k in first. However, I just figured out why, I think. It's first AS but Coach AA. When I looked it up before I happened to be on the mobile site and it doesn't show the class in the flight details there that I can see. That seems like a kinda important detail there. Silly me for assuming they'd list that when booking a non-refundable flight.
So that probably explains why it wasn't an option when I searched on AA for First Class awards. I guess if I want a cheap First seat I'll have to put up with a few stops
(note to self, pick out a route that has PP lounges for the layovers, hehe)
Torn on picking up more cards for the flight. I know AA should be easy but I've had a ban on Citi since I closed last card with them years ago out of aggravation (and reading all the "citi being citi" posts on reddit just tells me they're still the same or gotten worse since I had them) and honestly, Barclay's scares me a bit
BoA is kind of tolerable but I'd have to be for sure I want to fly Alaska for that. Current plan for the budget is 50k UR and / or 50k MR for this flight. Hoping for "or" because I'm cheap but that's the only thing these points are budgeted for so if I need to use both I'm ok with it. Also have a pile of SPG that I can use if needed, if the MR isn't enough and I can't use the UR to augment. Seems like I'm up for more research still
sad
And we're meeting up with some Dis'ers for 
We've been laying our phones on top of our glasses 
