Type of offense versus roster
Right because your contention is that all players fit, gotcha.
No, my contention is that Sean uses the skillsets of players to their strengths. Honestly, it's not even my "contention". It's an observation of fact from over 15 years of play-calling. This isn't an opinion. It's pointing out what has actually happened for over a decade.
Just look at the WRs and TEs that have been used over the years. Meachem, Devery, Lance, Mike, Jimmy, Dave Thomas, Shockey, Cook, Colby, Colston, Hill, Cooks, etc. None of these guys fit a "type". Brandon Cooks could fly, BB it he was used mostly in a "possession" type role. Lance was used mostly in the slot, but once he was gone there wasn't a rush to fill his skillset. Devery gets attention as a deep ball guy, but his real strength was running after the catch.
If there is any real "scheme" to Sean's offense, it's that he has a preference to using 12 personnel, with one TE being primarily a blocker and one TE being primarily a receiver. Even this is done to give flexibility to creating matchups vs defenses. With two TE, you have to respect the running game which might force a defense to keep a LBer on the field putting them at a disadvantage to covering the TE. Pull the LBer for a Safety to cover the 2nd TE and now they are opened up for the rushing game.