When you have expendable tokens to snack on, Krav will gain you a decent amount of card advantage and Regna has lifegain synergy with token generation on top
her zeal and desire for action caused unending conflicts with her teachers
For the most part, trying to stay Dimir is ideal and lets you draft the necessary pieces for your deck when they show up, but on a draft-by-draft basis, you want to be aware of the reasons to go into additional colors
JUST a deal-four-Drain-for-four would warrant a second look at five mana (folks have paid six for this without complaint)
Sally Sparrow The heroine from my favorite arc
I remember looking at vanilla creatures that weren't particularly good deals, required obscene amounts of colored mana, and had names that seemed like they'd been crafted by pulling scrabble letters out of a bag blindfolded and thinking this was one of the best things I'd ever seen