sorry old boy, you could be a big daddy if you didnt have a anchor, more traditional big daddy
so yea, it could be a alpha series, big sister, even throw champion idea links on here
Having just recently played through all three games I have a few ideas.
SPOILERS
I think the most obvious one would be Fontaine 
in the style of the last fight and have all his spells be deep red but not like fire, more like he's throwing around ADAM.
"GET HIM MR. B!!" Sure you can't make into a big daddy, but you sure can make Tibbers into one, give 
some glowy eyes and a bottle syringe and its the perfect little sister, especially with the new lowered CD and tibbers being around almost permanently.
"Would you kindly?" Slap a suit on him, and hand him a golf club and you've got 
Ryan
I think any void champion can be Gil Alexander-esque.
And finally, we already have Lady Comstock, http://imgur.com/rR7JeZX
Fin
Having just finished playing Infinite, I got a few ideas myself.
My favourite character in the game, Song Bird, could be a cool skin for 
. I think an Idol of Durand where Galio whistles would be fun.
Also, why not an Iron Patriot 
. If there's one thing I hate more than fighting those buggers is laning against an Aatrox.
