I don't have them broken up. Should I and what size?
They will break up over time and you will have more concerns with recombining them, I dont recommend breaking them up. Ive also read that you will get more coins the older your coins are (higher weight, higher stake), I dont know if that is true however. Would be awesome.
It's true. Older blocks generate higher stake. So it's not a big deal if your blocks don't stake straight away. As long as your don't hit the maximum POS reward of 250HBN your good. Same goes for getting orphans while staking, you lose nothing. The block will stake until the stake is successful.
And when Tranz compiles the new version of the wallet, you don't have to worry that much about recombining either. The latest commit will add much more control over when blocks will and won't split after staking.