I'm in the same boat. I have 35 x 5* heroes at level 90. So unless I pull a very new hero or costume, they won't even crack my top 30 without 2LB. And when I pull a hero that is say, 1 year old, I don't feel any excitement (assuming it's not a crazy powerful hero for its day, which it usually isn't). I just feel a big let down knowing that there is no point in levelling it anyway. A good example is my last 5* pull: Xiaoqing, the snake healer from last year's Lunar New Year. He would make my top 30 if I took him to 2LB. But am I really going to spend those valuable resources on a year old hero that wasn't exactly dynamite on his release day?
To me the problem isn't the number of AAs though. They actually seem well balanced compared to other resources. I think the problem is that they keep giving out older heroes long after they've reached obsolescence. Maybe Xiaoqing isn't completely obsolete yet, but I also pulled Tinsel at Christmas, and M&M at Halloween. What are we even supposed to do with those?