I can handle about:config, but if they take it away, that will be very frustrating.

For me, the bigger address bar is just as bad as an advertisement: it's trying to steal my attention, except in this case no one else is benefiting from doing so.

If they remove the option, I hope someone smarter than me can come-up with an add-on to fix it.

There's no "if" they take it away, it's already gone in Nightly builds.

Furthermore, Firefox extensions don't have the capability to mess with the address bar.