I would go Ford 9", with gearsets from somewhere about 2.5 to 7.5:1 readily available. There are several types of traction devices you can get as well from Equaloc, Auburn, Torsen, Detroit Locker to name a few

The gears in the diff you now have are possibly a stump puller ratio(4.56 or maybe steeper) and not suitable for a daily driver - unless you like contributing even more $$ to the likes of the ExxonMobil cartels.