Just to clarify the slow vs fast grind conundrum that is for some reason a conundrum.
The enjoyment that comes from having a slower grind is that once you've made it, it's an achievement that you can be proud of. When people know you have r1 in a particularly hard to rank skill, they will be impressed. When people know you have gotten the master title for that skill, it's even more impressive.
A faster grind will let players get to r1 more easily, which makes it (at the very least feel like) less of an achievement. Not as much effort was put in compared to the slower grind variation, hence it is not as impressive.
This explains it perfectly, but the main flaw is that tedium isn't achievement on any level.
Oh, you started breakdancing inside a clump of slow moving weaklings 500 times instead of 250? Wow man, you should get a medal!
I can't honestly think of any skill rank (or level climb, while we're at it) that isn't entirely composed of tedious busywork, besides the book ranks. The idea of feeling a positive sense of achievement from sitting in a ditch and pressing 5, or failing to gather materials, for 4 hours at a time, is astoundingly backwards to me. Wouldn't it be more rewarding to advance your mastery of a skill by actually doing something of note, if you're supposed to be notable for it? The skills that deal with books do this brilliantly, since you would normally only get those through an actual achievement of some sort.
You've already got the grinding aspect down with gaining levels and gathering up AP, so choosing not to defend "kill 10 wolves" as a progression mechanic honestly shouldn't be a hard decision here.