First, you have to appreciate the probolems that the mass attendance of HBCU's has, the way you seem to suggest it. It's something that's not exactly feasible, financially or geographically, no matter how much I support the idea. So, what are the incentives to make this happen and to get more African-Americans to go to already struggling HBCU's?
Me, I'm in favor of a permanent, "unified" Black Congress of sorts that purposely sets out to house the whole spectrum of Black ideas, philosophies and ideologies under one roof for the purpose of tackling those political, social and economic interests.
To be clear... YOU are the one calling for UNITY and lamenting the apparent Dis-Unity without respect to the reality of why HBCU's aren't the focus of UNITY. There are some practical issues involved. And in order to be responsible in YOUR call for UNITY those issues and how to get around them have to be considered. And I'm saying that even while I think it's an excellent idea. But you and I both know the numbers you envision (though not disclosed) aren't going to come JUST BECAUSE.
There could or should be a "unified effort" to prevent and reintegrate ex-con's back into society in order for them to be productive members of society and, more importantly, the Black Community. This is crucial because the amount of brothers going to prison. But I'm not naive or ignorant (as in ignoring)  the actual services out there that indeed try to do this and  the overall lack of [surplus] resources available for this venture, human and financial.