It's too hard to make a definitive list without years of research, but I'd say that around 50 or below is fair considering all he's accomplished.
Taking Mayweather's 0 Beating Hopkins at MW Taking Tito's 0 (I scored it for Oscar :twisted Beating Mosley x2 Pacquiao That's a pretty impressive run of victories right there. I have him around the 70 mark (so on the cusp of 2 of the breakdowns), but putting those victories on his list...? Top 25 isn't too big of stretch I don't think.
Who now even has the record of facing the best opposition of recent times than Oscar does? I don't like ATG lists as that just puts more fighters on their than there needs to be. It shouldn't be a 1-100 thing. That adds many undeserving names there. Still Oscar is great and I don't hold the robberies from Trinidad and Mosley 2 against him so yeah he's ATG. Too many solid wins and a winning record against the best opposition he possibly could to say he's not. His resume is a who's who of his time and that's what every great fighter's resume should be.
Yeah, whenever I've tried to put together an ATG list I've quickly hit a point where I don't really know (or even care) whether fighter A should be ranked above fighter B. Should Panama Al Brown be ranked above Joe Brown? It becomes far too subjective when you are comparing division hoppers with division hoggers, and fighters consistently good over a long period with those who were unmistakenly great for a shorter period. I wouldn't have DLH in the top 30, but there should be a place for him in the top 100. I wouldn't argue strongly with anywhere in between.
I never even tried an ATG list I just looked at docs and studied styles lol. DLH is actually the only fighter of recent times not named Holy that I think deserves to be an ATG.