That would be a good tank for a new carpet but it wouldn't be long before it outgrew it. If you get a jungle they tend to do some climbing and perching. If you get a coastal they will do that when hatchlings but tend to stay on the ground when they are adults.
IJ's and diamonds, I haven't had personal experience with so I am not sure how they are for climbing but would like peoples input if they got any on that. Same with Bredli's as well.
Big snakes are illegal in Canada so I have never owned burns, anaconda, etc. So I can't speak about differences between them. I do really enjoy carpets though and find they are a lot more interesting then most other snakes I've owned.