It's apparently u333. Got u271 and will try that 1, will re-post/edit after some testing
EDIT : u271 with mods doesn't work (gets to the notcrash with "binary stopped responding", like before). u271 with no mods works fine (gets to the main menu and everything works so far). Apparently, something in my mod folder stopped working overnight with jre8 and now prevents the game from starting ......
EDIT 2 : "disable all" from the loader also works (unsurprisingly). Definitely some random junk in there died on me and now the fun part of finding which 1 begins
EDIT 3 : only loading the libs works, trying most of 0.95.1A-compatible with libs doesn't, that leaves at least 1 of those as the culprit
EDIT 4 : weird, adding each mod 1 by 1, save list, restarting the game, exit, add another, save, restart game, etc works like nothing ever happened > but dumping them all at once/enable all makes the game time out. Some wonky stuff is at hand
EDIT 5 : re-adding my entire mod list 1 by 1 instead of "enable all" got me back to where I was before posting the bug report. I'm more confused than anything, it somehow fixed itself after breaking nothing overnight .......