You seem really passionate about this game so I would feel bad about ignoring you but I don't have the project files for this game anymore and I'm working on a Doobis Films fan-game now but honestly your ideas are really great and I have actually made multi-lane shooting plants and starfruit plants in past PvZ projects of mine.
I think what this game really needs is a plant tester and a zombie wave tester and more convenience to the zombie wave maker but you should probably find someone who could help you mod this into the game and maybe I can upload it as an official 2.5 version of the game in a zip file or something like that.