I will be the first to say -- I know very little about HBCU schools, but I know they'd go years without getting anyone drafted. Sanders brought eyes to HBCU schools and the players. The Lions drafted a DE from Jackson State -- they activated him from the practice squad two weeks ago and all he has done is get 3 sacks in the 2 games he has played.
I think you underestimate what he will be able to do. He has hired HC's to coach alongside him, Kent State HC is now his offensive coordinator, Willie Taggart former Oregon/FSU coach with be his defensive coordinator. I think you will see Deion bringing in top 15, top 10 type classes, as majority of the top recruits are african american and truth be told, while Sanders is cut throat as you see in the CU team meeting, he looks like a fun coach to play for.
I think he will be competitive next year, but it will take a few years to build depth in the program, to have sustained success. It will all come down to what his kid looks like against an enormous step up in competition for a QB.