[I am a mobile Firefox developer.]
I think you should definitely pursue tweaks that reduce the amount of finger movement required to do common tasks. Just to steal one example from Opera, when you long-press a link, the context menu appears directly under your fingers, so you don't have to go anywhere to get to it (similar to the right-click menu on the desktop). This is incredibly convenient, because navigating the context menu doesn't cause you to lose your place on the page.
Given a couple more months in development and some speeding up and I'd be happy for Chrome to replace the stock browser, as long as Flash support is added. All those that call for its demise still don't realise how useful it still is on certain sites.
https://developer.android.com/about/dashboards/
ARMv6 builds of Firefox are coming soon:
http://armenzg.blogspot.com/2012/06/initial-automated-armv6-...
I would have liked to see them do the same for the browser app a long time ago, but in a way having Chrome as a separate app achieves the same goal going forward if it becomes the default.
1. http://gs.statcounter.com/#mobile_browser-ww-monthly-201105-...