Josh
There are already quite some alternatives for the IDE.
There are mods which extend the IDE's functionality (I'm not so knowledgeable about these)
There are other tools which provide the Arduino IDE functionality and more. For instance eclipse plugin, avr studio, visual studio plugin,...
So instead of starting a new initiative I would advice you to look at the current initiatives and help those out. I'm sure they can use a good programmer (I'm sure I can) This is probably the best place to start looking at what is available Arduino Playground - DevelopmentTools
Best regards
Jantje
PS As I'm developing the eclipse plugin, I discussed the "IDE's next to Arduino" last week with David Cuartielles who told me he directed his students to eclipse . 
A really nice way to flatter someone 8)