If you had £1500 to spend...

I don't know what your thoughts on buying used is but I recently bought a used canyon ultimate aluminium, for ~£800, the seller also had the canyon ultimate carbon fiber and said he preferred the ride of the al, the ride of the cf was a little too stiff but if that's what you are after maybe the cf is for you.
A 56size with rival/force mix with decent wheels comes in at 7.3kg including pedals and two bottle cages.

Best of luck with your search.

Merckx EMX-1. bang on budget at evans but even cheaper at winstanleys.

I'd 2nd the roubaix - wait till they clear this year's models and pick up a deal - that's what I did

+1 to wait for discounts on 2013 bikes if you want a bargain.

All the bikes are brilliant these days, and there's no point a bunch of strangers giving you their preferences. You need to visit some showrooms and pick one that fits you and you are happy with it.

I'm a big fan of Spesh. So comfort = Roubaix and I believe there is a model currently around £1800 so that should fall under budget.

It depends how racy you want the bike really.

If you go for a custom set up I can recommend the Kinesis TK2 frame for an all-year ride. Long drop brakes needed (get the Shimano ones as they're great). I originally built mine up for about £2k but if you go for 105 or Tiagra stuff you should be able to get the price down.

If carbon is a must then look at Pinarello too. Last years models might be available in some shops and they start quite cheap now.... well "cheap" LOL

This close to the 2014 stuff hitting the shop floors I'd hold fire a few weeks and get something carbon that is reduced from circa £2k.

Just imho.

Cannondale CAAD 10, it's an aluminium frame but just as light as a cheap carbon bike, and more robust, should you take a tumble!