Its all speculation, but I think Ayala would be a HIGHLY dangerous fight for the 154 DLH. Ayala wouldnt have beaten Leonard, Hearns, or Duran...... but Oscar wasnt in those guys leagues. For the sake of excitement though....... one of the truly DREAM fights would be Vargas vs Ayala. And my opinion on that fight is that Vargas ate too many left hooks to beat young Ayala.
It's tough to properly predict Ayala against quality opposition. He looked like he had the goods, as they say, but he ended up in jail before he faced the type of opposition (i.e. Duran or Moore) that could show how good he really was. DLH at 154 didn't look especially strong, and I suspect DLH would have a lot of trouble keeping Ayala off him...especially early on. But we don't know how Ayala would handle the incoming from DLH or how he would react against a fighter who hasn't crumbled early and is still making him work in the middle to late rounds.