I find the more cards I have the more I want to make new decks. The mechanics that are generally in place for the colors lead me to White/Red/Black pairings far more often. Lifelink, good bumps and Enchantments, weenie, direct damage, tokens, area control. Just a lot of synergy there. But I see the allure of Blue/Green. The things that burn me up to see when it's played against me: total resource denial, fliers, Trample, +1/+1 counters, powerful Planeswalkers. I'm just a mess at playing Blue.