i am fed up with ros ps4 i am playing a crudaser full valor sader set fist of the heavens etc i am paragon 1,100 gr90 have been gr 90 for nearly two months i have a primal ancient chest every thing else ancient primal and all i get from bounties rifts greater rifts is crap not getting any further fed up.
I love your idea of reforging primals with a guaranteed primal. It needs a higher cost to make it balanced. 50 seems somewhat low to me. I would go with 200 but we can agree on the numbers later. Phylacteries as you said are one of the hardest items to get as a perfect drop. Same with quivers for demon hunters, mojos for witch doctors, etc. It can roll with so many undesired stats and you kinda want all the offensive rolls there. Another minor suggestion, make primal puzzle rings guarantee a primal drop by the end of the vault.
To answer your second question, no you cannot increase the qualify of the items. The perfect item can be anywhere even in the lowest difficulty, in campaign, opening a generic chest somewhere in the world… You can increase the quantity though and that should affect how many decent/good/godly items you can accumulate in the course of one season. The perfect formula is doing rifts again and again fast and consistently. Around 3 minutes is the ideal time for you to farm these so you need to find the lvl perfect for you and farm that over and over. Nowdays, every class has 3-4 builds that can farm a lvl 90 greater rift in 3 minutes effortlessly. That should net you around 10 legendary drops each time. Add a few more drops from kadala where you spend your blood shards and now you have a large pool of items and hopefully somewhere in there, there are some primals.
Primal items is the 1% of difference it took to make the average gamer excited about nothing at all.