Yea I wish jeep forums (not this one in particular, just in general) would stop with the whole "keep the spline count the same so you can use your stock as a spare" thing, I mean is $300 extra for a spare 35 spline really that big of a deal when spending $2k+ on your axle?
Now as far as the dana 60, I'm probably going to be flamed for this, but I don't feel like a semi float high pinion prorock 60 is significantly better than a 35 spline dana 44. You still have 35 spline shafts and you still have SF flanges. And yea the ring gear and pinion are slightly larger but you're also running on the coast side with a HP so the difference in strength might not be as big as you think. Yea the housing is significantly stronger but how often does the rear d44 housing prove to be the weak link in the system... Most of the time it's flanges, sometimes its shafts, once in a while it's the r&p, and then rarely you see the dude with the "friday" axle who spun the tubes.
So if you are looking at D60s I would go with a full float low pinion, either the mopar one for cheap, or custom order a prorock with low pinion. If considering semi float... I would just do 35 spline in your current axle... IF you can walk away with locker+shafts+labor for 2kish. If we're talking 3-3.5k it would be hard not to just bite the bullet on a 60 for another grand.