Resolved 2 of the negatives... ran into another, but that's a squeeking BigRock crank issue so I won't bother you guys with it here.
I experienced this same issue with the saddle tilt on a recent ride. About 8 miles in, hit a bump, heard a creak from the saddle and thought I cracked a rail. I did not, but the saddle was tilted and there was no using a multi-tool to get it unscrewed and put back in place correctly. I was able to get it back to level enough by shifting my weight around as well, but it never stayed level. All this moving around locked the screws in so tight, I stripped the heads trying to get them off. That made for a fun time getting them out. I had to resort to penetrating oil and lightly hammering in the hex wrench to get the screws loose.
I just pulled it all apart earlier this week, replaced the bolts with titanium M5x25mm hex head bolts and put it all back together again and torqued it to 8nm. We shall see if it holds.
I'm still looking for any recommendation of a titanium seat post bolt if anyone has one that works for them. The standard one has a soft head and I'm afraid it's going to get stripped.
Having said that, I do really enjoy riding the bike. It's comfortable, relatively light, agile, and is responsive to accelerating. Just a few small quirks to be worked out.