I won't address the cal mini lift, as IMO, it's a waste of money for a bunch of stuff you don't need.
Cranking the T-bars creates lift in the front suspension by applying additional torsional load to the lower control arm. Crawl under & give your front suspension a look some time...see if you can figure out how it carries it's load without any springs.(coil or leaf)
OME 912's are the preferred replacement coil around these here parts, & that's all you really need to buy...Indy 4x if you want them now, Rocky Road if you want lower price & don't mind waiting.
I'm not sure about using 919's on the VX, might be too much spring, I used them on Jim's Trooper on Matt's (Indy4X) recommendation. Some have gone to longer shocks in conjunction with 912's, but unless you're going for more lift via 912's & 2" poly spacers, I don't see the need. I've been running 912's & a 1" spacer for about a yr. with stock shocks & no problems. I added the spacer due to extra weight I carry.
I would really like to see someone post a definitive comparison of all OME rear coils that fit the VX...that right there would be some handy information !
There are no back ball joints, it's a solid rear axle.
The "uber lift" you mention isn't really a possibility, as you are limited in how high you can go by the front CV angles...much higher than what we're talking about here & you should start thinking about a differential drop bracket in the front, a body lift, or SAS conversion. (use the search on those for more confusing info.)
Also, when lifting, I would recommend a set of stainless steel braid brake lines, (again, Indepent4X) they are a little longer to compensate for the lift, & give the pedal a firmer feel than the stock rubber lines.
Good Luck