You've taken on the world when it comes to debt and accomplished what many haven't.
I give you an A++ for ambition but, the speed of credit is molasses. Slow down and get your bearings again before you start jumping into another issue that will prevent recovering from the lates and charge offs.
1 card/loan in your name is enough to build your profile back up... it just takes time. Lots of time with those kind of dings on your report.
Focus on the dings and dirt for the time being. Try hitting up the OC's and seeing if they'll send an update to the CRA's for removal or recode the payments as PIF at this point since you remedied the issues in full. If that doesn't work then hit up the CA's for the same removal of the collection since it's now PIF. Some will, some won't.
Make sure you have autopay setup and put a small monthly bill on the Disco to keep it active monthly thus unsecuring on time as your score comes up with the activity.
Once you gain some traction again with your profile and get your scores up things will happen more naturally. Don't mess around with the AU's too much or it might mess up your reports as well. Leave the 2 AU accounts and keep the balances low if possible.
Let time heal the issues now that they have been taken care of. It might take a little while but, be patient and don't get twitchy with ramping things up in a short period of time or it will backfire.