I would pick Charlie Taylor, Bobby Mitchell and Jerry Smith as the best trio ever. Heck, one year, they were first, second and fourth in the NFL in receiving!
Yes (times three).
It took teams double and triple coverage to handle Mitchell, and when Graham converted Taylor to WR, it was like the Redskins had an unfair advantage with Jurgenson passing. (Of course, they had a disadvantage in that Graham didn't bother with a running game, or a line or a defense, but, hey, nobody's perfect!

)
Yes again on Jerry Smith. The best pass-catching TE ever. Certainly better than Bob Tucker from the Giants, who was a similar small TE.
Story from my Dad (repeated from an older thread): Sonny is broadcasting, a season that Allen has brought in Jean Fugett (or someone like that) to replace Jerry Smith as the starting TE. The Redskins are behind, and another announcer asks, "Sonny, what would you do in this situation?"
Sonny answered, "The first thing I'd do is get Jerry Smith in the game."