The following is a list of all two-color combinations, how I've learned to understand them and my opinions on them. Feel free to tell me why I'm wrong and bad at the game.
Azorius (UW): What if blue also had board presence? (Really annoying, but I attribute that to me being bad)
Boros (RW): What if Red killed on turn 5 instead of turn 3? (Actively makes Mono Red worse. I don't get this combination)
Orzhov (BW): What if Black had infinite resources to sacrifice? (Hell yeah)
Selesnya (GW): What if I had absolutely no game plan? (Jack of no trades, Master of about as many. Another one that just seems to clash)
Dimir (UB): What if Blue also had access to unfair cards at the cost of both players sanity? (This should be considered a war crime)
Izzet (UR): What if Blue also had kill pressure? [Alternative title: What if I wanted to play Yu-Gi-Oh with mana?] (Fuck Izzet)
Simic (UG): What if Green had MORE scaling? (I have no gripes with Simic. Fair and balanced MTG)
Golgari (BG): Hey, killing my guy was mean :c I'll just bring him back, ok? (Reanimate :3)
Rakdos (BR): What if I killed myself and played YOUR deck instead? (Rakdos the Muscle, The Infamous Cruelclaw and Laughing Jasper Flint are the most interesting concepts to come out of MTG)
Gruul (RG): What if I played red with a backup plan? (I have no gripes with ~~Simic~~ Gruul. Fair and balanced MTG)