I might go with Manticore for the nostalgia. Not sure yet. I'm also not a fan of the Quen abilities. However, the Adrenaline Point gain is so good on the Bear armour though.
I'd recommend keeping the Cat School techniques if you can enchant the Bear armour to be light gear. The bonus to critical hit damage is insane, and means you can often do a Rend worth 10000 damage, which absolutely slays bigger, slower monsters or bosses.
Something I didn't make clear, is that you should probably always use the Troll decoction too. The build sort of revolves around you pushing past the Potion Threshold, which means your health will be draining. For me, the Troll decoction stops this, although some others say that it doesn't. Seems to be 50/50. I also use mending runes in the armour slots for the additional HP regen. Each decoction you drink will give you 1000 extra health, which stacks with skill 'Endure Pain', which increases your HP by 50% if you go past the Potion Threshold.
The build can handle 3 decoctions at the same time, plus 2 potions. With the 4 added slots in B&W, you can add Fast Metabolism to the build, which means you will able to drink more potions quicker, as your potion toxicity will decrease faster (the potions themselves and their effects stay active though) while the decoction toxicity will stay the same, as the two are calculated differently.
In terms of the new super mutagens / synapses, the Euphoria one seems pretty good, and is easily reachable. Metamorphosis also sounds cool. but requires a lot of points to research.
