How do you feel about Rulebreaker as potential House Rules for existing commanders?
I feel you shouldn't call it Rulebreaker.
Decks that break the rules but are tacitly accepted are as old as EDH. Playing two brother yamazakis as commanders was done before the partner mechanic was even printed. Having an Urza deck where he advances through the years every time you recast him sounds fun. Putting a fun silver border card in the list, of course. Even playing a commander that wasn't one of the original five elder dragons was "breaking the rules" at some point. WotC runs a pride event every year where everything has partner, and I know a few people that keep those decks year round for occasional play. I don't think a saheeli partnered with Huatli deck is an issue for most tables.
The protocol for these "rule zero" decks is simple: talk about it with your table. See if they're fine with it. Ironically, Rulebreaker is the opposite of that: it's playing within the rules! You don't have to disclose that and discuss it in advance (any more than usual when revealing any random commander, that is. Talk to people, folks.) It's part of the rules that you get to break them in specific ways. They're even balanced around it! As much as anything is balanced in commander. Hence why Tolabow only gets one extra color and a relatively lackluster effect.
So, sure, keep making rule zero decks if they have a compelling reason to. A reason good enough most tables will agree to let you do that playing against them. Likely one inoffensive enough to not feel like you're just cheating to gain an advantage.
Could you model some of those against existing rulebreakers? Sure, but I don't think playing all the best of X in five colors is the most compelling reason to bring to the table. "I just wanted to be able to play better cards" is usually not enough.
So I'd just keep calling those "Rule Zero" decks, because that's what they are. And leave the Rulebreakers as their own, legal, freestanding thing.

















