Exactly Keon was drafted to play on the outside

Agree. Smaller shifty guys are typically better fits in the slot but some bigger guys have had success.

Larry Fitzgerald for the last few years of his career converted into a slot receiver role. Big guy for it and a bit slower in late 30s but arguably the best hands ever and he became one of the better blockers at the position. 

I typically find the best profile for that position are the “quick” / route running technicians. When I hear slot I immediately think white patriot receivers (welker, Edelman, amendola)

In current league Amon ra, shakir etc. 

I guess for the bills shakir would already be their main slot target

HardMoney

That’s a problem for someone who gets paid to catch.

BlokchainB

Big body contested catch guys work in the slot too. That was Jennings role with the 49ers before Aiyuk went down and he had to play outside.