1 - called smooth corrective modifier
2 - you can bake smooth corrective to shape keys, but to weighting? it’s a deformer, right? not familiar with the concept, only used delta mush in maya.
3 - you can make corrective shape keys and use bones as drivers
4 - yes, you can use any tools you want to make the correctives
5 - there’s a non linear animation editor
6 - you can make a pose library under the armature tab, and a shape key library in the object data tab
7 - I’ve seen some addons, never tried them though
8 - in the animation nodes branch maybe
9 - partial yes, due to dependency graph limitations it’d be a bit fiddly though. (controller being parented to a surface, and deforming a wrapped duplicate)
10 - possible in a lot of ways, you’d probably want to get more familiar with layered rigs first though. Also, I’m sure there are heaps of addons for this kind of stuff.
11 - I wish…
12 - only watched the last part, but you could do that with a lattice unless I’m missing something (a grid deforming an object within a certain proximity)
13 - there’s a voxel heat weighting addon which is pretty neat
14 - many ways to achieve this. from jiggle bones to dynamics on a proxy/control mesh. no deformer though
15 - there are some addons for that but I’ve seen alrightish results with particle sims. depends what you want in terms of complexity, game of thrones or minecraft.
16 -haven’t watched the whole thing, but there’s a follow path constraint.