I did a little cuben pack experiment last summer and knowing the kind of trips you do (maybe this is intended for something else?) I kinda think you should reconsider. I used 1.5 oz cuben and put a decent sized hole in it on it's first day out in Death Hollow due to a (not very hard) bump on the canyon wall. I later put another hole in it on the same trip after walking through some willows. On the other hand, I've used a VX07 pack (which I didn't expect to be strong enough...thought I'd need vx21) for well over a year now and beat the hell out of it in the mountains and canyon country with no apparent wear. Unless you're using one of the laminates with a nylon face, the lack of abrasion strength is significant unless it's going to be strictly for (wide) trail use.
If you're going to go for it:
-I used v46 bonded nylon thread. I like nylon thread for packs and v46 seems like a good strength/hole size compromise.
-An extra strip to sew through is good, but I think it'd be a good idea to also tape seams AFTER they're sewn. This way, the tape is taking most of the stress, rather than the needle holes (which will take all the stress, regardless of # of layers, if not taped). I'd go all out here. Something like a compression strap can be a lot of stress on a seam.