The only problem in my opinion is in leading out into a multi-way raised pot with J-10 on a J, 8, 8 flop. I'd probably much rather check to the preflop raiser to get a sense of where I stand, and either call or fold, depending on how strong he seems.

Also, in the hand where you flopped the boat with J-J, I think it may be best to lead out on the flop. The only hands that will give you action here are 3 kings or some sort of straight draw, and leading out will help get maximum action from these hands. It will conceal your hand from a player with 3 kings and will allow you more time to get him committed to the pot, and if a player has a straight draw, then you want him to pay to draw dead (if the player misses, you win nothing).