We shared our opinions about the games themselves, but what about the main antagonists that the game make you face in the main quests ?

With the exception of FOBOS, you always end up with more than one character that could qualify as the main antagonist.
With FoNV, the number can go quite high, as you have five main quests, and only one that is partially needed.

Personnally, i think i'll always have a soft sport for the Master, not only in the Fallout series, but in any medium.
He is a special being like no others, he have a dense backstory, is an idealist, and have many ways to be dealts with.
I also quite love the lieutenant, that serves as a great pragmatic foil for the idealistic Master.

Also, it is impossible not to enjoy both of these guys lines and the way they deliver them.

Then, i would pick Benny, Caesar & Robert House. It has been a long time since we got so much depth in Fallout main antagonists.
Amongst the three, i consider Benny as the most sympathetic. Too bad he is the one that actually tried to kill you twice, and that would betray you again given the chance.
Caesar & Robert House have an impressive backstory and important role in the setting, but they feel a little closed minded, when you spend too much time with them.

About the Enclave, i mostly consider them as an interesting faction as a whole but i wouldn't consider their individual villains as that iconic.
I tend to prefer the presidents (Richardson/Eden) over their grunts (Horrigan/Autumn). I prefer Horrigan toward Autumn, as Horrigan as at least the cartoon traits that make him funny, while Autumn is just a blank state.
Eden, on the other hand, was very entertaining to listen on the radio, but the actual encounter with him was pretty short & boring.

Other baddies serve their purpose rather well in the setting, but don't leave a great lasting impression.

I give a bonus for the possible FOT canon ending, with Barnaky-Calculator in charge.

Not going to talk about dlc baddies now, as the main games are heavy enough on big bads.