I found the fleece smelly as well since mine refuses to go on his litter box and he poops a lot in his cage. The positive side is he doesn't poop much on his wheel since he usually stops to poop somewhere in his cage.
I use finacard.
There are a lot of options when it comes to the cage, but they need quite a lot of space for such small animals (I can see mine really enjoys his current cage more than his first one, which was smaller - 40x20 inch). The wheel and everything takes up a lot of space.
Some people connect 2 bins with a pipe. For the burrowing behaviour, I have fleece strips in his sleeping hut and he has a dig box with small river pebbles. He doesn't dig much in the substrate.
Good luck with making your choice