Four chips just pushes the inevitable off one progressive bounty round. 4 chips becomes 2 to the winner's pocket and 2+4=6 the the winner's bounty. Then, when that player is eliminated, 3 chips go to the 2nd winner's pocket while 3+2 = 5 chips go to the second winner's bounty. Now you're gonna have to worry about splitting 5 chips...
When you get an odd number of chips, I'd prefer to correct the rounding to the nearest chip on the spot (whether its an extra half-chip in the winner's pocket, or an extra half-chip in the winner's progressive bounty). You could even draw a card on the spot (or roll a die, or the dealer reveals the next card in the stub) to determine which way the rounding goes.
EDIT: I suppose it possible that someone with 3 bounty chips could take out a somebody with 2 chips (one cashed out, one added to bounty), so that the player now has an even 4 bounties in front of them again.
I still think half-bounty chips get rounded on the spot. Personally, I think they should go the the winner's pocket (as opposed to their progressive bounty) because once they become part of the bounty, that person never wins them unless they win the tournament.
Would you do a prize pool *and* bounty pool? And if so, 50/50? Or just do a bounty pool?
If you do a prize pool and bounty pool, the winner will likely have a few bounties already, plus will win all of 2nd place's red bounties, plus take first place prize money.