Odric, Lunarch Marshal would make a great White General. Unexpected, but load him up with an army with abilities (such as Oketra) and equipment or enchantments that grant abilities and he quickly gets to dominating a field. Plus I have wrathed a board with him on the field, making all my critters survive, to the dismay of my opponents.
For Abzan, I have the very queen herself,
Anafenza the Foremost. Her deck is where I utilize Odric (even if he could be great on his own), but board wipes definitely hurt my opponents with her on the field. I also have
Sigarda, Heron's Grace providing cover for a mostly
human deck and myself.
I can tell you from experience, Thrasios and Vial Smasher did not work out as well as I had hoped.
In
Grixis, I have
Nekusar, the Mindrazer as one general and
Thraximundar as the other. They are very different decks. Nekusar makes people cry every time they have to draw and/or discard cards.
Thraximundar, on the other hand, punishes every opponent every time a creature of mine dies. Thrax takes more time to build up, but once he does is a
juggernaut to deal with.
With
Bant, I had a Rubina Soulsinger deck that I called La Belle Dame Sans Merci. I put
Feed the Pack and Cathar's
Crusade into the deck, robbed them of non-token creatures and fed them to her wolves... Making a very big army of very big wolves to help her out. I took it apart for my Abzan deck, but it is one I have thought of rebuilding bigger and meaner than ever.