My friend Peter (Kiwinote) has a very interessting new project called AppGrid. Its a replacement for the ubuntu software center written from scratch. Peter contributed a lot to the original software-center so he knows the problem domain quite well. You should give it a try, it can be added via:
$ sudo add-apt-repository -y ppa:appgrid/stable $ sudo apt-get update && sudo apt-get install -y appgrid
Then it can be found in the dash as “App Grid”. I hope you like it!