I'd consider wrapping the roof in carbon-look film and swapping the bonnet for an unstriped one. The look at the moment isn't necessarily bad but it's very individual.

Doing the above, swapping alloys back to standard and dropping it 35-50mm (sell new wheels £500-ish+, use existing originals or buy for £250 ish, use remainder to buy springs and a compressor) would give it much more generic 'racer' look that would appeal to far more people, and particularly appeal more to the people you say you want to sell it to.

Might cost you £100 or so to do but you'd be far more likely to get a sale.

Don't mean this as a diss, just advice from someone who's been there (albeit not with painted on stripes!)

Chris