A little late to this party. Kind of surprised it is still going.
Wife's Subaru turned 190K miles today. It is an EJ25 and I did the head gaskets before they blew. Still like Subaru and will likely buy another in a few years. Hopefully they will solve the FJ25 issues before then.
I kick around buying another Subaru from the mid 2000s. Something in the 05-08 range. Use it as a daily driver. Then I realize I don't have extra time as it is. Then again, we put an offer on a house about 6 miles further away from work/life. Not really worth it unless I got a smokin deal on it and could turn some wrenches to make it worthwhile. Who knows. Stranger things have happened.
As far as head units, I put a pioneer in my truck. I added a camera and it works well 99.9% of the time. Every once in a while it seems to be challenged and doesn't activate. I don't know how the aftermarket world works with all these touch screen controlled systems today. My son and I have talked about it with so much being integrated into the head unit. Crutchfield should be able to tell you what works and what doesn't. They usually have good install guides as well.