I get what youre saying. The reason its hard is because you dont use them, but thats actually realistic lol.. You get 5 star WRs literally every season because thats your playing style. So a team like Texas Tech in the 2000s would never have a FB interested, it would 99% realistically be a walkon or moving somebody. The fact that they barely use a FB is why the walk on doesn't hurt them, same with you
WRs and RBs are interchangeable irl and on the game. Theres no advantage or disadvantage. Same as putting a DB there, no advantage. If you call a 5 wide play the defense will adjust accordingly (cpu or user), if you call a 3 wide play with a RB and WR in you gain the advantage (cpu or user). The weight rule is so we can have more flexibility without too much of an advantage.