About 6 months ago my company changed from having a Before Takeoff Checklist to a Before Taxi Checklist. Now all we do on the taxi is an abbreviated Before Takeoff which has flaps, takeoff briefing and cabin. To be honest I think it is much better and not really any slower. I find all the checks and checkslist items bar Ground Clearance and Flight Controls can be actioned while waiting for the despatch engineer to disconnect and signal.
We fly 733's if that makes any difference to your thoughts.
BTW why don't you do your V speeds in your before start items?