A few ideas (not particularly well thought through, and you will need to do a bit of digging to find out if they are worthwhile or worthless):
- Will the CAA give you a Class 2 medical? If so, take a look at what you can do with it (it seems that the PPL FI is just around the corner, so you might be able to instruct)
- See if there are any other JAA / EASA states who will give you a Class 1 sonner than the CAA - finish your training there then transfer your licence back to the UK (change your "state of licence issue")
- Get an FAA CPL/IR and see if the CAA will give you a Class 1 on the back of your ICAO licence (worked for me, though in very different circumstances)
- Go back to the CAA and find out if there are any cirumstances under which they will lift your 2 year suspension earlier (so get some medical evidence so that they reclassify your head injury as less serious than "serious") - you would probably need advice from someone who knows the CAA system but is not part of it