My old cotton bag is reasonable in humid conditions, but a larger nylon bag I use to reload 5x4 holders gets hot fast. Having your hands hot is surprisingly uncomfortable, too.
A collander or mesh basket inside the bag helps keep the air space. It can't be too large, as you need the flexibility of the bag to move around. The other thing that might help is a bag of activated silica gel. I also keep the bag in a plastic bag when it is not in use to reduce dust.
There are tricks to loading 120 film that are worth trying because it is flimsy compared to 35mm and sheet stock. An old* photographer suggested that I put a slight reverse bend in the start of the film before sliding it into the spiral. I unroll the backing paper until i get to the film, fold it back enough to put a slight crease in the end, and start loading. The fold stiffens the start of the film and makes it easier to keep it in the spiral initially. I do not unroll the whole length, just enough for a few winding cycles. I an also careful to keep my fingers at the guides so that I detect if the film is not feeding straight. I use a thumb nail to tear the tape at the end. The extra tape survives low temperature process fine, and helps separate the second roll if you are double loading the spiral.
This works with white nylon spirals and the old clear Jobo ones. The nylon ones do have to be clean and dry. I have enough spirals that I can swap working sets if I have a lot of development to do.
I also roll up the backing paper before starting on the next roll. I also have a scheme for where the various parts of the tank and film are placed in the bag.
* Old in this case was 24 years my senior