I think it's fine, but two major issues:
£3k is a BIG premium - £1.5k-£2k would be slightly more palatable.
Rear visibility does indeed seem shocking when the roof is down - surprised they weren't willing to sacrifice a tiny bit more boot space to improve your view out the back.
That said - most will be bought by women, so the feminine looks aren't an issue. I think it looks fine. I'd buy it, though maybe for my wife! The roof solution is far better than lopping the entire top off the car, adding 200kg of strengthening and fitting a large metal, two piece roof that gives your car a massive backside. Note: see 206CC. It's more "basic" motoring and that's "in" right now. I think it's mostly quite an honest little car, if playing slightly on the retro/nostalgia thing!