I use the Investor product through Terra Nova. It might suit you. You are right, RT3 is a little overboard for some of us. Maybe after using this new product, I will make the upgrade. Give it a shot. I know they have demos.
Also, Instinet Clearing seems good. I was not a client when they were with SWS, but from what I have seen on other sites they had some big problems.
Good luck.