In reply to Badpanda: Several points that spring to mind:
Do you REALLY need 60s?
I'm fairly skeptical when it comes to long ropes on rock routes. I've used them various places from major alpine rock routes to Yosemite but never found them very compelling. I've yet to find any rock routes where they are ESSENTIAL for the ascent. Also, whilst I've certainly read about modern routes that have abseil stations at 60m intervals I have never found that has applied to the routes I've done or the routes that I am most likely to do.
Conversely,
"for glacier travel and moving together on long ridges or pitching" I'd take a skinny 60m half rope over a standard 50m single any day of the week. [FWIW something like 40m of 9.2mm Mammut Revelation would be my first choice.]
Finally, I don't know why you think
"easyish multi pitches" NEED doubles. A single and 6mm pull cord for abseils is a perfectly good option. If I needed/wanted a single rope on a trip, I'd considering sacking off the doubles completely. A couple more slings on my rack and 50m of 6mm as a pull cord would suffice for pretty much any rock routes.
There are stacks of options, you just need to be a bit more open to thinking about what compromises you can make.