Tom, your doing exactly the same as me. Had the anni for 5 years now and time for a change, just going to collect a new valance in the morning to replace the theft.
Ive looked at alsorts from civic type r, megane r26, focus ST, to S3, S4's etc.. Running costs will increase tenfold. I now do 100-125 miles a week and get expenses for half that, so not too bad. R32's road tax nearly 4x what we pay now, fuel double each month, also insurance may well double your current premiums. On top of extra service cost with the haldex system and so on.
I think i have settled for an ED30/pirelli now, 2.0t engine, realistic tax and servicing costs, for the miles i do, not a huge amount more in fuel maybe extra £50 a month.
Im a fan of the DSG, yes it less envolving, but i've become alittle lazy and in traffic it would be great, also they handle a stage 1 remap better than a manual as in time you will need a new clutch. Also the DSG burble on gearchange is [In-love]
MK4 r32 yes in your budget, good ed30/pirelli, maybe not, £13-14k would find you one. Get yourself registered on mk5 gti forum and have a read, its what ive spent the last 12mths doing.