If you want to do some thorough research on boas I’d highly suggest The More Complete Boa Constrictor by Vin Russo. Regarded far and wide as the boa bible and I agree.
The Complete Carpet Python by Nick Mutton, Justin Julander, and Benson Morril is another bible on a genus but is out of print. You may be able to find a second hand copy but I’m not sure how much they’re going for. I got mine on eBay last fall for ~$70? They are currently working on The More Complete Carpet Python however.
Researching can be half the fun and you sound very interested in some very cool species. Now that morelia is in the options I’d be hard pressed to suggest a boa or a carpet over one or the other. Both are interesting and rewarding captives in their own very different ways.
Best of luck in your research!