Best out of three

[Bounsweet]

I love Raichu and I think Pichu is adorable (it's a tough choice between those two) but Pikachu isn't up there with them to me. I still like Pikachu, but I like the other two more.​

 

[Feebas]

Pichu all the way. It's too cute to bear. Excuse me while I go die of overexposure to cuteness.

 

[obZen]

Definitely Raichu. Surge's Raichu was THE coolest thing ever!

 

[moon]

Not sure between Pikachu and Raichu but I think I'd say Pikachu just because it's slightly cuter. Raichu is really cool though, always loved it in the manga specifically. Agree with Corona Infinity!

 

[Eruption]

Raichu has a better design and is the strongest of the three. I used to hate Pikachu as a kid due to its excessive use as the mascot and I suppose I originally liked Raichu as a way of boycotting that. Pichu similarly gets too much attention, despite Raichu's clear superiority.

These days I don't mind Pichu or Pikachu, but Raichu has survived as my 2nd favourite pokémon of all after various generations. So Raichu wins.

 

[Banz]

Pichu is the cutest of them all, but I like Pikachu the most.