I believe that the old joineries were problematic in the sense that gildaur was BiS for most weapons except for bows and magick weapons. That was mostly because it had the most damage and also lifesteal which was really handy in melee builds.
I like what joineries are going for now with additional virtue scaling really opening up some weapon combinations we didn't have before but in the process joineries really lost some identity. Right now a Verite is the same as a Gildaur which functions the same as Feybalt.
I do not think that joineries should be adding straight up stat buffs because that opens up more BiS options and the rest is left to collect cobwebs in the depths of your inventory.
My suggestion would be to add in some QoL buffs in adition to the current ones to the different joineries that lean more into playstyle than damage.
For example, Verite could be the joineries for the elusive and evasive. make it speed up dodges and widen perfect dodge window. Gildaur is the joinery for the brutish and headstrong. It could increase the parry window and add additional stagger on successful parry.
For the ranged options, of course the agile minded can always use Verite, but for archers, Quicksilver could be favoured by the eagle-eyed. It could increase zoom distance and increase projectile velocity. And the ones rooted in the fey magicks may prefer Feybalt. It's conductive properties could decrease charge time for heavy strikes and increase the seeking distance of magick projectiles.
Or something along those lines. Nothing that would affect damage numbers to an absurd degree, just some buffs that lean more into certain playstyles than others.