And I agree that a Mako with more of his old gang affiliations would have been very interesting. It's really amazing how little was done with it, especially given that Republic City Hustle was commissioned to show it in action. Can you imagine a Book Air that featured Triad Mako teaming up with Avatar Korra to oppose the mutual threat of the Equalists, and the ways they conflict from opposite sides of the law as they work against Amon? With bonus Lin and Lighnting Bolt Zolt conflict as each one's overseer? Oh, that would have been the best Makorra ever!
Yeah, I'm pretty disappointed that they never really went anywhere with Mako's old gang affiliations. It's weird how the triads appear in the first two books, and then basically disappear. The last we hear of them is that Mako took down the Red Monsoons off-screen. I can't help but wonder if they had some vague intentions of bringing them back, but ended up writing Book 3/4 storylines that left no room for them.
I like your idea for Triad Mako a lot.