Gumwall tyres: I agree would look good. But practically speaking there are no good enough gumwall tyres for the back of a fix (in terms of thickness of rubber)...too anyone after gumwalls I recormend the NOS handmade veloflex tyres at work. £25 a pair at the moment too. Fucking amazingly nice tyres.
...another good option for anyone else are Schwalbe Lugano's.
Only 23c I think (25 if you looked hard?) so prolly not enough for you^ but IMO really nice for the price.
Good grip and I had no punctures when I used them for a daily commute thru london.