I would not bother with a half link chain. Tried one on my SS - Gussett slinky?, it stretched alarmingly (2 months - dozen or so rides). Get a proper strong SS chain instead and use a chain tensioner if required.
Regarding chain tension, get it as tight as you can. It's the family crown jewels that are at stake and they need to be protected from top tube collisions.
I'm using a half link chain at the moment and as it's quite new I'm not getting any wear issues yet. However, using either a half link chain or just a single half link in a normal chain, I've found it still is never quite right - I could do with a quarter link :roll: But that's with vertical dropouts - semi-horizontal you should be fine. Why not try one of the single half links? Charliethebikemonger has them on Ebay for around £4.
If you can afford it, a White Industries Eccentric Rear hub would work best-of course, you'd have to build a wheel around it! Chain tensioners are OK, but add drag and don't look as clean.