Nadiers Nightblade (CMR) is even better, as it loses the requirement for a commander to be present, and drains rather than bleeds
So, well go through them all and rank them from best to worst
Troyan, Gutsy Explorer There are a couple directions you could take a Troyan, Gutsy Explorer deck since Simic has good options for both X spells and large mana spells
All of this could be said for Grim Flayer as well, but the upside that Grim Flayer has when you deal damage to your opponent is so great that Grim Flayer is in a better position against Bant Company than Sylvan Advocate is
Archangel Avacyn fits comfortably within the best Angel commanders MTG players use for reactive play, flashing in to protect your board before flipping into a sweeper
Video selling is a fairly underexplored way to exchange MTG cards, so try this out if you have a lot of product lying around, and check out Bryans review of the process