537 Cards (124 C, 200 UC, 168 R, 45 M)
Sets:
AFR, STX, KHM, ZNR, M21, IKO, THB, ELD, M20, WAR, RNA, GRN, M19, DOM, RIX, XLN, MID, VOW, AKR, KLR, HA1, HA2, HA3, HA4, HA5, JMP, STA, J21, A22, Y22, NEO
Includes several rebalanced cards from Alchemy.
I thought about that when writing!
I keep my color and guild sections even. For me, it's easy to keep the guilds equally represented and relatively balanced. However, the impact on draft and gameplay of going +1 or -1 card in a guild is marginal - even less so going +3 or -3 in a mono color. You could make a strong design / choice argument for doing or not doing this.
I do cheat with some cards, especially in mono-color. If I want to slot another land or colorless card in, I might see Phyrexian Metamorph in my colorless section and go "hm...you're a blue card now."