Hi RatboilerHi and welcome
Best of luck with that one, I fitted a Kenwood unit to my 2008, the fitter added a piece of kit that bought all the functions back onto the original steering wheel that I already had.
The unit had a phone facility (blue tooth)on it which worked well.
The big plus was the replacement had much superior sound quality without changing the speakers and cost around £70 or 130 fitted.
I did a write up on it if you do a search.
Cheers Ratboiler.Mine was the same as yours. I think you will be getting into the unknown by replacing the steering wheel with a later type.
I would keep it simple and replace the radio/CD player with a unit that incoporates a phone facility, better still you will find write ups on here from guys incorporating sat navs as well.
It all comes down to how much you want to pay in the end.