For non-weapon training, quests still could add special techniques or recipes, or even spells.
Alchemy: recipe for a memory-erasing potion that reduces you a level (lose exp as well) in return for some skill points
Cartography: NPC draws a location or two on your map, in detail
Meditation: some slight boost to health regen along with mana
Dodge: boost to missile avoidance
Hide in Shadows: a bonus to mêlée attacks while hidden
Pick Locks: less pick breakage
Skullduggery: PLACE traps! mwahahahaha
Spot Hidden: radius extended by 1 square [or more?...]
Some very cool ideas in here - hope BW sees these.
Skill trainers add a certain amount of points through their training (like five) and books continue to add two. You CANNOT add skill points from book or trainer unless you already have at least one point in the skill already.
So if I have 11 in Bows and I read the book, I go up to 13. Then I use the trainer all five times I go up to 18. If I have 0 in bows, neither the trainer or the book even make sense to me. The book is teaching you specific extra knowledge you couldn't've gained on your own. Same with the trainer. However, if you've never learned this skill on your own, you would never be able to understand the book or the trainer in a meaningful way in the first place.
This is another very interesting suggestion.
I'm not sure I like the second part of it (i.e. the "can't add Skill points unless you already have that Skill" part) - though I can see how that change would introduce some very interesting 'game-balancing' issues(benefits?) to the game, and would definitely make the "Jack of All Trades" challenge meaningful!
But I do like the first part of it - especially if gaining the 5-levels at once cost you a *pretty penny* (like 2000 g.p. instead of just 1500 g.p.!)
Anyway, this is another suggestion that's worth mulling over...