Component upgrade - keep frame?

aka_finto Posts: 72
edited November 2012 in Road buying advice
I'm currently riding a BMC Streetracer SR01 Tiagra. Covering c.40km/day on my commute and aiming to do another 50-100km on the weekend getting slightly further afield.

I'm lucky enough to be in the position to spend a bit of money on myself and am looking at upgrading the bike. I quite fancy upgrading the groupset and wheels and have been drawn towards electronic shifting. Question is, would it be worth putting something like an Ultegra Di2 groupset on the Streetracer's frame, perhaps with some decent aero wheels? Probably able to spend up to £2k in total. Or would I be better served buying a whole new bike?

The main reason I'm asking is the Streetracer frame fits me like a glove (or should I say, I fit it?) No niggles on the longest of rides and the geometry suits me perfectly. I'd be loathe to lose that in buying a new frame. I've also got saddle, bars etc. just how I like them so worry that a whole new bike would be tantamount to starting from scratch.

Happy to take suggestions or feel free to slate me as a fool! Cheers