Get 80 attack, keep 72 strength, get 90+ defense and become a rapier staker. If you don't want to get defense, get 80 attack, 95+ strength, 95 prayer, and become a turmoil zerker.
I hate to say it but One Defense pures are pretty much worthless in the current Runescape generation. There is just too many over powered weapons that will be able to tear through you like mad. If I was you I would either become a Zerker pure or and Initiate pure. For zerker pure you would get 45 defense and for Initiate pure get 20. One thing you will have to get is 80 attack. There is no doubt about it, if you want to have a fighting chance you are going to want to have your chaotic weapon. I prefer rapier, but it is generally preference. As for strength I'd suggest 80 at a minimum as well if not more. Prayer would be good a 43. If you decide to do one of those two things you should be pretty good. Good luck with whichever you choose.