How much do you want to spend?
Your week points are going to be your u-joints and your ball joints with that HP44.
Fish Bone Fab makes a king pin conversion kit. I have yet to see any reviews, but the kit looks to be strong. Its spendy at $400, but could be worth it. Poly also has new ball joints out that look beefy as hell.
U-joints are D30 sized, so why not eliminate them altogether. Just go with RCV's and get your new age hardware fix. They're super strong and solve the u-joint issue thats been the cause of much D30 vs D44 debate. Not to mention you can get them in 30 spline outers with drive flanges. Win Win until you see the price tag, but with a life time you break it they replace it warranty whats not to like. I'm sure you could call them up and get shafts made for your hybrid axle deal too if you're dead set on it.
Add a locker with those two things and you've got yourself a stout axle.
I'm actually in a similar boat as you. I've got a 79' HP44 out of an F250. My plans are to leave it full width, RCV shafts, drive flanges, king pin conversion, Jana 54 kit, locker, and gusset the knuckles. I might cryo treat stuff like the locker, R&P, and other small parts. It all depends. Either way its a lot of money into an axle and then the question becomes, why not just get a D60.