We use bog standard wood pellets & I have to say they are brilliant as they absorb wee and wee odours and can be composted,
burned or put in with landfill rubbish without making me feel too guilty!
As for poo smells.... you could feed him indoor kibble that reduces odour, I get the RC one, it does seem to work.
I am lucky (or not .... depends how you look at it) as my cats seem to wait until I get home, run around a bit and then have a poo which means I can dispose of it pretty quickly, I flush them down the loo as well, don't see why not really. Could be that his poo will settle down once he is used to his new environment and food.
Is he going to be an indoor cat?
Jo X