So, the purpose is, that habitats are supposed to support a "tall" play-style ? ...
Sorry, but if I think about playing "tall" then I relate this to A. my empire-sprawl (and B. my administrative capacity and C. my empire cohesion): A. Empire Sprawl ("ES") is influenced by the number of star-systems (+2 "ES" per one), colonies (+2 "ES" per one), branch-offices (+2 "ES" per one) and districts (+1 "ES" per one). B. Administrative Capacity ("AC") is influenced by (specific) ethics, civics, authorities, techs, traditions and a-perks. C. Empire Cohesion ("EC") is influenced by the number of star-systems (+1 "EC" per one), (better) starbases (+3 "EC" per one), outgoing hyperlanes (-1 "EC" per one) and isolated star-systems (-3 "EC" per one). So, if habitats are supposed to support a "tall" play-style then isn't it rather a question how the "ES" (and the "AC" and the "EC") should be affected by habitats ? ...
01. As far as I know, a habitat still counts as a colony, so that we still get +2 "ES" per habitat, but this could be changed, that a habitat could count as a (better) starbase instead. ( This would even restrict the total amount of them in a "reasonable" manner since they would be tied to the starbase-capacity ). ( And yeah, I know, that it's a big deal, that habitats = (better) starbases ). 02. As far as I know ( and in contrast to districts ), buildings don't increase the "ES", so that it could just be allowed to build buildings on a habitat. ( And come on: It's already an artificial structure + It's already called a "habitat": Just grant it XX housing right from the start ( without any buildings ( or districts ( currently ) ) to be needed ). 03. I haven't really a clue how the "ES" from the number of star-systems should be affected by habitats. ( And yeah, I know, that it's "ingenious" to build as many habitats as possible in as few star-systems as possible ). 04. Dito as above in regards to the "ES" from the number of branch-offices ...
05. I don't really want to force a rather unintuitive connection between the "AC" and habitats ...
06. In reference to my point 01, each habitat would increase the "EC" (+3 "EC" per one) since a habitat would count as a (better) starbase, but I haven't really a clue how the "EC" from the number of star-systems, outgoing hyperlanes and isolated star-systems should be affected by habitats ...
Long story short:
To support a "tall" play-style, it's maybe a better idea to look for possibilities how the "ES" or / and the "AC" or / and the "EC" could be affected by habitats.