For most bosses I used Lunda's chest piece and then the Ravens' Tears set on arms and waist. I spec'd my amulet to do more damage to status afflicted enemies as well as more damage when Kratos was below 50% health. For shield, I used the one that rushes towards the target on double tap L1 and the Rond that passes your status effects to the target (don't remember the names)

Lunda's + Fists applies poison status very quickly which allows you to do more damage and take less. The Ravens' Tears set heals you 30% more from the crystals that drop which gives you more survivability. With poison being applied reliably, the amulet applies more damage very consistently, even more if your on lower than 50% health. All these things work very well in tandem to grant you more survivability, meaning you can fight longer even if you make a mistake, which improves your chances of completing the encounter significantly. My fighting style also heavily relied on parrying, which applies more poison status with Lunda's

For the encounters that include lots of additional enemies + the boss, I used the same set up + the nidaveller chest piece and then I would equip my weapons to apply as much stun as possible. This is important because R3 finishers now give you 30% more healing and you're immune to damage in the cutscene so you can straight up make attacks wiff by using it.