What to train strength on?

But doesn't that require defender of varrock? It's not quite an easy quest, and you don't quite get the drops if you don't finish the quest when training with them.

I would do ankous with salve (e) amulet. Buy 15 bones to peaches, and start at the lowest level of stronghold of security. 15 bones to peaches at your level is about 300-400k xp.

That's what I'm doing right now, and with about 18 BTP, I have gotten well over 1.8m in drops.