I had one made from a blanket with an angled stitch to create a hood many many moons ago.
Only complaint was that it was heavy.
Doubled as a summer-weight sleeping bag, though
Sounds great for a winter cloak, especially if you're trooping outdoors!
I got a hooded cape for the last con I went to. Easier to move around, and cooler (thermally).
I'd perhaps avoid wool or cotton for that very reason. They'd be hot as heck.
The only thing about a cape, is ensuring that you have a good, strong clasp, since it won't stay on like a cloak. They "flow" - like capes are want to do.
Otherwise the sewing shouldn't be too hard. By hand might up the difficulty though...
Wool would probably be more of a winter cloak, I agree. And yeah I'd imagine having to hand sew would throw a cramp into things, but still should be fine.