For anyone wondering some generalized sealed tips:
17-18 lands
23-22 spells
6 non creature cards
17 dudes
14 CMC3 or 4
Anything over CMC5 or more needs to really add value to deck
Each targeted enchantment wants 4 targets to make sure you aren't drawing the enchant but no target
Your best cards may never get played. Bombs are useless if you can't field another 21 cards around them.
I shift the guidelines a bit by set but thats my general baseline.
I'm trying to decide between B and W for the pre-release. Both promos are great. Both have a pretty good selection of commons and uncommons. Removal seems to be a
little better in B (surprise, surprise).