It definitely looks like you have a good idea of what you're doing, so at this point I'd recommend playing it and changing based on what people like to play and what you find to be good rather than based on theory crafting. It's good to have archetypes in mind, but they don't really matter if no one's playing them or don't play them optimally. I would recommend adding Thriving lands, City of Brass, Gemstone Mine, and Aether Hub, since they're good options for lands that would let you cut down on fixing a bit since you don't need to be specific colours to play them. The untapped ones are also very good for aggro.
If you want to support green aggro you probably want more aggressive green 2 drops, but only if you want to support green aggro.
I'm in support of larger multicolour sections, but once you start going past 5 or 6 (non-land) cards I do think you get into multicolour cards not being unique enough to justify their inclusion. Sure, every BW deck will play Mortify, but it's not that much different than a mono B or W removal spell, so the problems that come with it being multicoloured aren't really worth it.
If you like the heavier focus on multicolour but have problems with people playing a bunch of 3+ colour midranged soup or have a bunch of gold cards never being played, all of Leelue's suggestions are good ways to deal with it. I would also pay attention to the signets in particular, since they really incentivize 3+ colour good stuff.
If you want to support green aggro you probably want more aggressive green 2 drops, but only if you want to support green aggro.
I'm in support of larger multicolour sections, but once you start going past 5 or 6 (non-land) cards I do think you get into multicolour cards not being unique enough to justify their inclusion. Sure, every BW deck will play Mortify, but it's not that much different than a mono B or W removal spell, so the problems that come with it being multicoloured aren't really worth it.
If you like the heavier focus on multicolour but have problems with people playing a bunch of 3+ colour midranged soup or have a bunch of gold cards never being played, all of Leelue's suggestions are good ways to deal with it. I would also pay attention to the signets in particular, since they really incentivize 3+ colour good stuff.