Wither wraith and Blaze Born will get permanently stuck if they die in the nether. No solutions I can find without resetting the world. Players who choose these classes will be stuck forever

Same case here, person will somehow be stuck in their own corpse as dead but somehow alive. Can't move, only punch.
Only solution has also been to delete the player.dat everytime.

Same here- DO NOT allow them to kill themselves by punching their own heads, this also corrupts the chunks because their spawnpoints will be invalid.

As with #297, can't be reproduced in an origins only environment.