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.
difference ensure competition and variety of point of views.
The problem with monoculture is that it _enforces_ the lack of difference. So if the guys in control of the monoculture stop progressing, or progress in a direction that you do not agree with, you're basically fucked and it takes enormous effort and time to change it.
It happens so many times and with so many things (not even software related) that I'm amazed it's not the first thing that comes to mind.
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.