Advice on new bike or just upgrading my current one

Hi,

I've been following the Road.cc forums and site for a while now, but only just felt the need to post here and ask for your advice.

A bit of background: I ride both road and MTB, however I would say the majority of my time and money is spent on the road. I'm currently riding my first road bike; a Kuota Korsa Lite ('11 I think); and I'm on to my second 'proper' MTB; Specialized Stumpy Comp Evo, purchased within the last 12 months (owned many cheapo/Halfords MTBs growing up, but not important here.)

For the price, I feel that my Kuota was fairly well specced at around £1200 when I bought it: Shimano 105 group set, Deda and FSA finishing kit, however it's only rolling on standard Shimano R500 wheels and it's alu frame / carbon forks.

When I upgraded to my Spesh from my entry level MTB, it was a real eye-opener to see what difference a more expensive, better specced bike made to my riding. With the novelty of the new MTB wearing off, I'm left with an itch for spending some well earned money on my road bike.

Now, I could go either way: I could go for some nice aero wheels for the Kuota, which I read makes a hell of a difference on the flats, etc. (but not necessarily beneficial on the climbs) however I fear that the rest of the frame will be the bottleneck. My other option is to replace the bike with a more capable frame and components, hence this thread. I've had a good read through the forums and there are a few similar threads, however I didn't want to hijack/dig up those other threads:
/content/forum/80000-choosing-new-bike-how-hard-can-it-be
/content/forum/93613-carbon

So, first things first: budget. I'd love to be able to find something up to £2500 as I feel that's a sensible 'next step' from the Kuota at £1200.

Next: brands. I've a taste for the following, however I'm not limited to these, of course:
- Felt
- Bianchi
- Wilier
- Cervélo
- Canyon

Ideally, I would like to go for something a little more unusual, hence the brand suggestions above. Furthermore, I'd like to try to steer away from the likes of:
- Trek
- Focus
- Cube
- Cannondale
- Scott
- Boardman (of course!)
- Specialized (yes, I'm over the moon with my Spesh MTB, but I don't want to look like a Spesh fan boy so I'm not 100% keen on this option, including just in case)

So, some bikes that I've pencilled in to the short list:
- Canyon Ultimate CF SLX
- Wilier GTR
- Bianchi B4P Sempre Pro
- Felt F3/F4
- Cervélo S2
- Specialized Tarmac Comp (as above, I'm not 100% on sticking with Spesh for road, but willing to consider if worth it)

I'd love to hear some of your opinions on the above. I appreciate that I may sound fussy, but I'm open to almost anything, if it's worth it! If there are any other bikes/brands that I've not mentioned above, please let me know and I'll take a look.

I would also be interested to hear your input on whether anyone feels ot would be worth it / not worth it to upgrade the wheelset on my Kuota as a stop-gap between this and getting a new bike. Wheels-wise, I had one Mavic Cosmics in mind if I went down the aero route, or Campagnolo Shamal Ultra Mega G3 for normal profile 'climbers'.

Cheers!