Gotta say...I'm looking at the three LUAs...and they seem just really boring.
Abe is ok...thematic and flavourful, and it's okay, mostly riding on the free unit, which doesn't have the synergy of Basil's, so it just seems meh. I guess it's based on the IZ so they didn't want to make it too powerful.
Nzinga's is perhaps thematic and flavourful (I'm really not knowledgeable of her history, so I'm just going with the colonisation of Africa thing here), but is a little boring. Increased yields on her own continent and reduced on other continents just doesn't mean much to me. I guess
Saladin is...blegh. it's not often I get to use flanking anyway thanks to AI abilities in combat, and it just doesn't do much for me at all.
Perhaps I'm overly harsh - it's possible that being used to getting Civs with leaders, getting only leaders is inevitably underwhelming in comparison. On the chance I'm not being too harsh, I'm a little concerned because I'd have expected them to start with some exciting ones - get a bang to build excitement for the other leaders. Not every leader can be exciting, and we were going to get boring ones as well (that are needed), but that they started out with them suggests that maybe that's the tone for the pack.