The cage will have plenty of hides and other things to make the space feel smaller for the snake.
It is not the Helix is too expensive but Im sure there are other products out there that may be a little less expensive. And do the job as well as I need it. I do not need it the be exactly 90 deg all the time. If another unit can hold me with-in 1-3 degs for less money I would be ok with that. If I really need a hundred dollar unit to maintain the temp then I will spend the money.
I do have to ask about the CHE, I have not heard about them making it harder to keep humidity up. I know it will be hard enough with the larger tank, I would hate to make it harder for myself.