Yep, I'm guilty of overstocking. Although, I try to stack them... some bottom dwellers, some mid-range swimmers, and some upper level. However, the loaches do occassionally go everywhere and not just stay at the bottom; and the gouramis don't just stay at the top of the tank but will venture into the cave from time to time.
Also, I added a UV sterilizer that runs off of a second water pump/filter. So I'm overfiltering like crazy now too.