I used to do some BMX dirt jumping for a few years in HS/right after. I have pretty much the same thing as you where I was out of it for ~5 years. I've found as a newbie with that background(just got into MTB last summer), I like the feel of a 26" with a lower travel, kinda stiffer fork. Granted I only test-rode a couple 29ers and didn't trail them, and I don't have a lot of experience with forks since I'm a newb, but that's what I like so far. I would suggest ripping some single-track and not just sticking to the fun drops and jumps. The single-track is pretty damn fun too. My ideal bike so far seems to be more aimed at a middle of the road "do a little of everything" more than any particular direction. Kinda like a DJ bike with a DJ style fork but a bit larger frame like a trail bike. If you want to do some huge drops and stuff you might want more travel, though. I have found that with the BMX dirt jump background, I tend to feel just fine hitting things on my POS with 80mm travel fork that the only other guys hitting are on FS or at least expensive hardtails with really nice/large travel forks, but I think that may be related to the riders in my area too. I'd say most important is to go test-ride some bikes if you can and see what feels good.