Fit yourself a double din unit such as the Pioneer mate, with a double din fascia adaptor. It'll look plenty OEM enough but have a great modern head unit.
Estoril looks beautiful.
Get yourself on EvoTechnik or E46zone if you want to have fun with other e46s, as there are so many enthusiasts about.
I've never liked the Clubsport rear spoiler, but meh.
Get yourself some black kidney grilles asap though! that's about the only thing I'd change on this lovely, mint looking car