If you want to avoid formaldehyde in your stablizer I think you'll need to switch to a complete Kodak or Fuji process. I'm not even sure about Fuji. From the enviromental view point my understanding is you'll still be using formaldehyde. The only difference is instead of it being highly concentrated in the stablizer it'll be in the other steps.
No idea about the bleach times.
I replenish my bleach. The bleach I use is low replenishment. 7.5ml per 36 frame roll of 35mm or similar. Other bleaches have higher replenishment rates. Depends on the formula.