From your days, it sounds like Deluxe may be the best bet.
But how many days are you even going? If you are ONLY going in March and August and you are paying $150 for March's admission, that means a Premium AP upgrade would cost $289 on top of that. I know ticket prices often go up, but a regular 6-day hopper is currently just $214, so the upgrade appears to be at least $75
more than just buying a regular hopper for August.
Now, the Premium AP price does include parking, so if you will be driving into the parks every day then it might make sense, but it's not really much of a perk if you will always be walking to the park from your hotel. There are also some food and merchandise discounts, but I'm not certain if those discounts alone will save you $75, particularly since you cannot upgrade until your March blockout date (unless you want to have to buy a blockout ticket!).
Meanwhile, if you are planning 3 days in August and 3 in March, then you wouldn't immediately save money with Deluxe either (though the food and possibly merchandise discounts might salvage it for you). $150 admission applied to a Deluxe AP means that you have to pay $149 for the Deluxe AP...but then you'll be paying at least $45 for a blockout ticket in August (I wouldn't be SHOCKED if that price were to rise).
So that's a total of $194 for your upgrade and blockout ticket, while 3-day hoppers for August currently cost $184 (and include one Magic Morning). You probably WILL make up that $10 difference in discounts, but the cost savings may not be great.
That said, it IS fun to be an AP-holder, just knowing that you can technically go to
Disneyland almost any time you like. For better or worse, though, I think with the AP it is quite possible that you'll make a third trip to Disneyland before it expires, just because you can. At least, that's what appears to be happening with my AP, which was supposedly purchased just so we could visit in December after our June trip! Now we're planning another May or June trip before our tickets expire.

So saving money on admission has led to some increased hotel, transportation, food, and merchandise costs!
(I'm not sure if the Give a Day promotion would work toward your AP, but it WOULD probably pay for a one-park ticket on your blockout day in August, provided that day isn't blocked by the program. Of course, then you'd probably want to upgrade to a hopper which would be I think $25, so your savings isn't much.

)