I don't think Benteke is a s slow as you think. If he was, how would he have kept up with Villa's attacks? He's no Usain Bolt but he's hardly a slouch.
And I think there would be quite a few different players who could play that way. Lewandowski was hardly a target man was he? Sturridge could do it (if ever fit) and even someone like Lacazette. Just because you use wingers and get the ball into the box doesn't mean you need an Andy Carroll type.
He's easy to mark, teams can get all their players back as soon as he enters the penalty area, which means you need to get the ball in early.
Because villa's attacks were hardly at blistering pace, they were at the maximum level he can move at. He is a bit of a slouch, come on, 3 or 4 1v1s unable to capitalize on, or really look like he was going to score from. He is just a powerful shot, good in the air, good at volleying, and a decent passer.
Yes you don't need an andy carroll type to use wingers, as you said only 30% of benteke's golden goals for villa were headers, can we really get him on the end of a ball with his movement? I don't see it. You're saying 4-4-1-1 with benteke. benteke is just gonna get isolated. No end of villa's matches went one way or the other with him. I have no vision for the benteke project, other than our centre mids having more space inside to score, and us playing wider thus being more vunerable to conceding, please explain more about how I'm meant to believe in benteke winning trophies with liverpool, and him helping replicate the dortmund way.
http://www.skysports.com/aston-villa-results/2014-15