Gluttony isn't the subject of the dietary laws; disease is. Meanwhile male homosexuality is explicitly part of the sexual laws, and it was important enough to be mentioned twice in a very short span (Lev 18:22, 20:13). A sin of commission is generally considered to be a greater sin than a sin of omission.
Alright, let’s assume, for the sake of argument, that homosexuality is a worse sin than gluttony. Let’s say it’s twice as bad. If it’s okay to deny membership to homosexuals would it then be appropriate to simply limit the participation of fat people? Should they be allowed to sing in the choir but be banned from teaching religious education? Should they be limited to communion only once a month? Four times a year? Christmas and Easter only? And about Christmas and Easter, should they be required to fast while others feast?
Should we assign point values to sins like envy or anger or sloth and what about pride? Is pride in one’s work not a sin but pride in one’s hobbies a small sin?
I'm not sure your idea of stack ranking sins is workable.