Diversity for the sake of diversity isn't going to get anywhere. That is basically gambling that something good will fall out of a different implementation just because it is different.
Instead, focus on solving problems. If the best way to solve a problem is to use webkit, then why do otherwise? If the best way is to go back and fork webkit from 2 years ago, and start your project from there, do that instead.
But don't be different just because you want to be different. Target your ambition toward something more meaningful.
