I'm glad you brought up this subject, as I know most players have similar confusion.
There is no 'better or worse' or 'better option'. You have to make a
personal decision on which core AI mod you want to base your installation on. Neither BP or Weimer's Tactics or the smaller tactics mods are better or worse than the other.
Although BP incorporates most of the same components that Tactics incorporates (please, read the ReadMe of both), it does make some extra modifications. (If you want details, the BP-
WeiDU forum is your friend. Start at the beginning.) Tactics has some components that BP doesn't. Some people like BP more, some like Tactics more, some hate them both.
So a player's options -- again, there is no better or worse -- are:
-- Play the game with vanilla tactics. It might just be an interesting experience.
-- Play with BP, Tactics or some combination of both.
-- on top of the above two, throw one some smaller tactics mods. Or not.