Don't worry, just judge for yourself! We are long time WDW vets, and started alternating WDW with DL about 4 years ago after we fell in love with DL. We love both places, and it sure is nice at DL to be able to get anywhere in a short amount of time. Your friends' description sure doesn't sound like our DL.
1. -Overall, didn't care for
Disneyland as much as Magic Kingdom.
Absolutely love them both. DL is Walt's park. Granted at times in certain areas of the park it can feel a little more crowded walking because space wide the walkways just aren't as large (i.e. at night around Fantasmic, especially when it is getting out- it can be crazy and Tommorowland can get a little congested). DL has the Indiana Jones ride, which I think is my favorite ride at any Disney park. DL's Fantasmic and POTC are better than MKs. DL has the Alice Ride, Snow White, Pinnochio, Storyland Canal Boats, a better Small World, the Mickey's Magical Map show, a very cute Rapunzel show, a great afternoon parade, and more. The castle may be smaller, but it has it's own charm and a fun Sleeping Beauty walk through. I couldn't say which one I love more, it would be like having to pick which child you love more!
2. Space Mountain, while fun, she didn't like as much as MK's.
We actually prefer DLs. DL has two side by side seats, where WDW is font to back. I think DL's is smoother. If I remember right, DL also has speakers in the cars so the music is better. If I remember right, you can kind of see the track a lot at MK, and I don't think you can see the track much at all at DL.
3. Character interaction wasn't as good. If you're not a kid, they pretty much rush you along, and aren't as friendly as Florida.
Character Interaction is different. There are some designated times and lines like WDW, but it is also like the old days in that there are several pop up characters, or characters which roam around. We have been over by the Alice ride and had the Mad Hatter and Alice pop up and start leading us all in an unbirthday party. It was very cute. Some of the roaming characters do not stop long enough to let lines form, you can walk beside them and grab quick photos and an autograph. You never know who you might run across which we think is fun. I've never noticed them being less friendly than in Florida on the whole. I would say it is just like Florida- there are absolutely fantastic ones, and a few total duds. At Minnie's breakfast, the Fairy Godmother got on the ground and tied DD's shoe! Now, we do have a kid so I don't know too much of how they are with just adults. I do know that I am a big Cruella fan and DD isn't, and Cruella hammed it up with me because she knew I liked her. Also at Goofy's dinner, Pluto messed with me every time he passed our table he would come up behind me and try to scare me or pat my head. At Goofy's the mad hatter specifically took photos with DH holding tea cups. We did have pilot Minnie be a little rude one year, but that is the only interaction I can remember not going well at DL. At CRT at MK, we had a Cinderella so bad when DD was 3, that DD insisted she was a fake stand in because the real Cinderella was busy at the Princess tent in Toontown! I also like at DL, how villians also pop up for photos. We've had the Queen of Hearts, Cruella, I've seen the Snow Queen out, etc.
4. All the dark rides in Fantasyland are neat, but they all have 45 minute waits all day long.
Not our experience at all. Go at rope drop. DL is far less crowded than MK at rope drop, at least when we hae been there. The first couple of hours are fantastic. I think it is because they have more of a local crowd that doesn't show up quite as early. We can get to DL, and do most of Fantasyland first thing without any lines. (And that is factoring in seeing Tink with maybe a 5 minute line first) After that, we have noticed that Peter Pan stays about 40 to 45 minutes all day (and there is no fast pass). We don't like Peter Pan at DL as much as WDW's version either (but I have heard others say the opposite). Pooh isn't in Fantasyland at DL, and it rarely has a line in our experience- never waited more than 10 minutes. Alice's line fluctuates. It does get up to 45 minutes a lot in the afternoon, but keep an eye on it and you can probably catch it at 20. Snow White and Pinocchico never seem to have that much of a line. Storybook Canal can get backed up- but usually we see it at around 20 minutes. Tea cups are about the same as DL. Small World fluctuates. I've see it at a pretty consistent 20 to 30 minutes in the afternoon hours. . I can't recall ever seeing all the Fantasyland lines at 45 minutes all day long and we have gone in summer and been there on weekends as well as weekdays.
5. Parades aren't set up as well. You have a very small area in which to stand, and once 2 floats go by, they let people cut in front of you and cross the street, blocking your view.
I don't agree with this at all. Maybe on the Main Street area as we have not watched from there, but we have found that we can hear the parade coming by and stop and get a decent spot to watch. If we are going to watch the whole thing, we like getting a spot on the curb and watching it back from the area near Small World. We have gotten a spot near the castle to watch after the parade has started and been in the area before. All in all, we think it is much easier to get a spot and watch the DL parade, than it is to watch the MK parade. There is not nearly as much planning or waiting required.
6. She preferred California Adventure to Disneyland. Said that park could use 2 days, but only 1 is needed for Disneyland.
They are both great. First, you want hoppers at DL/CA. They are like one park. It literally takes 5 minutes to get from the inside of one to the inside of the other. The walk between the parks is shorter than the walk from where the bus lets you off to the gate at most WDW parks. If your friends were not hopping, the were using a WDW mentality and not making the most out of the trip. Some times of year CA opens after DL (it has when we have been there). When it does, the thing to do is get an hour over at DL, and then move to CA at its opening.
I think as an adults only trip- you could probably accomplish everything you wanted in both parks with hoppping in 3 days. We have a kid with us which slows you down. We usually spend 3 full days, and then we will also be in park our arrival day from about 2:00 p.m. to 10:00 p.m., and departure day from about 9:00 a.m. to 2:00 p.m. (which basically gives us 4 full days), and we still always leave still feeling like we need more time.
We love both DL and WDW!
And I'm not a large woman. It was apparent these queues had been designed back in the day when people were much smaller or something. We tried to do the walkthrough in the castle but got up the stairs and the dark claustrophobic feeling and awful smell was just too much for us, so we turned around. We really realized 
) , and the jungle boat remote controlled boats too, but Trader Sam's is pretty fun and also handy for taking drinks up to the room if a grown up has to stay up there with the kids, but wants a drink- and the Monorail Slides and greenery around make for a great room view, if you have a pool view. Having a great character meal right there at the resort is great, and there is also a really good gift shop. You also can't beat the ability to run into Goofy in the lobby. One time he laid down on an ottoman and watched cartoons with DD for a while because the lobby was pretty empty. That is something we won't forget! 
Just saw this video the other day and I was quite impressed with their work:
