Prequalifying note: I don't really know much/have much experience with non Orange bikes so all of my recommendations/relevant 2c information is about orange bikes.
As someone who owns orange bikes all over the spectrum and has put a pretty decent amount of time on them, I'd say that a TPI 2 stroke or a 350 XCF-W/EXC-F would be the best bike for all-around trail riding.
The 250/300 TPI 2 strokes are very close in displacement, but in my experience, the 250 TPI is a VERY nimble bike, compared to an equivalent 300. A 150 would be even nimbler. I know you said no 300's but I figured I'd throw that info in there. The 250 can actually still be pretty intimidating once you get it into the power band in its high rev ranges. It's a little more peaky than a 300 as well. The reality is that with a 300 you can get away with riding it in its lower rev ranges with little to no stalling (especially TPI).
One big difference between a 2T and a 4T is that the 2T's actually do low RPM lugging better than their equivalent 4T's; 4T's will stall out at low RPM if you don't mess with the clutch a lot more often than a 250 or 300 2T, with the latter being even more luggable.
I don't know if you've already answered this, and if you have apologies but I must not have been able to grok it out of the thread, but does a plate matter to you? What about green/red stickers? I know you've listed bikes that are all over the spectrum re: sticker/plate, but if they do matter in a more than insignificant manner, I would order the orange series of bikes as follows:
Plate:
350 EXC-F hands down
Green Sticker:
350 XCF-W (should be a little cheaper than an equivalent EXC, but maybe not necessarily worth it b/c an EXC has better resale)
350 EXC-F
Red Sticker:
250 XC-W TPI (red) or 150 XC-W TPI (red)
350 XCF-W
350 EXC-F
I've always said that a 350 EXC-F is the perfect "compromise" bike, i.e. a bike that has a plate and still feels nimble enough to be a fun trail bike. You can also generally find them easier, as the 500's have a little more of a cult following behind them.
I would not buy a MX bike unless price is really an issue for you, the cross country oriented bikes are a better for trail riding. You'll end up putting a lot of money into an MX bike to make it more trail friendly.
I've owned a 2017 WR450F and ridden a 2018 WR250F and really do not like the ergonomics and think they are extremely heavy for what they are. They certainly feel heavy, especially compared to their orange counterparts. Of course, this is personal opinion and I'm sure there are plenty of people out there who will disagree with my assessment there.
