Returning player question

I left AO a few years back because I cannot do any more AI daily Mission as it's too difficult for my enforcer.(level 207 ,AI level 19) My enforcer has only mya armor. Tried to get the class armor in SL and also AI armor but also hit a wall because the bosses are too tough. I tried several times to find a group but either cannot find them or they find my gears too low group content. I am thinking of resubbing but am afraid the same thing will happen again. Looking for advice on progressing the AI level.