At first I thought this question was easy to answer, but there are so many fabulous aces!
I'm totally fascinated of Sanadas guts on the mount and really appreciate Akiras optimism. Mei is a badass genius (although I can't cope with his arrogant attitude) and Umemiya is just cool as hell! And I (finally) have to recognise Furuya! With his prideful and calm manner (especially during the last chapters) he is something else!
How could I possible choose between those guys? (¯□¯;)
btw I didn't take my lovely Eijun into consideration because he doesn't have the ace number (yet)! If the question would be "favorite pitcher" the answer would be different!
Narumiya and Amahisa are my favorites.
Akira would be the third and Shunshin my fourth favorite.
Masamune Hongou and You Shunshin are my favorites. The first one I like because of the proper power pitcher done right with a spice and the second one I like because control pitching is beautiful to watch.
I would say that my favourite overall in the series is Umemiya Seiichi lol! Mainly because no other pitcher, not even Narumiya (who is ridiculously cool), made me turn traitor against Seidou...until Ugumori! He's very versatile, good in defense and offence and really embodies the ace position! He pitches all the innings too so...props to him!
I have many favorite pitchers in the series but I will go with Mei Narumiya for obvious reasons. He's cute and adorable. What is there not to love?
He is extremely good at what he does, and his pitching has always gives me the thrills more than any other pitcher in DnA universe. He also has shown growth and maturity (a little bit more, haha) and has definitely the aura of an Ace of the Diamond.
My runner up favorite would be Amahisa Kousei. My! that slider is just gorgeous!
2nd runner up will have to go to Akira Nagao. A very interesting pitch, his knuckle ball, and that his team managed to reach the semis mainly thanks to this.
Eijun is not even the Ace yet. ;-; My poor baby. Anyways, my current fave would be Sanada or Mei.
Eijun easily. :) So glad I can finally answer this with conviction :D
I do love me some Mei, Kosei, Taiyou, Hongo, Ouno, Go-chan, Maki, You and Akashi too <3
OH, any Ace but Furuya, Ic an tolerate. Oops, he's 11 so he's nto even an Ace anymore. Never will be again, thankfully.