Gruul and Simic are fine. Orzhov is probably the best, but the others are around a similar enough power level and Incubation Druid is a solid card. It ramps you into late game plays and if you decide to go 3 colors it can help mana fixing. Sure I'd prefer a Lumbering Battlement or Ethereal Absolution but it's a fine first pick. The pack is pretty slim after that though. Burning Tree Vandal and Plague Wight are the only cards I'd include in a deck unless things went completely off the rails.