Yeah, really not trying to tell you how to play :)
I have also noticed that the quest type really adapts to the skills you play. After joining the bard's college and increasing speechcraftI was presented with a few quests that involved negociating with people.
I try not to count on stones too much, I use the lady for 15% speed in all skill gains.
Here is a list of permanent bonuses you can get from quests
Agent of Dibella, 10% melee damage increase to opposite sex, Temple quest: The Heart of Dibella
Agent of Mara, 15% magic resist increase, Temple quest :The book of love
Ancient Knowledge, 25% armor if you wear a dwarven set amror, smithing skill increases 15% faster (badass this could save you 5000-1000 gold if you are increasing this skill using vendors), Side quest, unfathomable depths
Assassin's aegis, 25% armor bonus if you wear the whole dark brotherhood armor set, dark brotherhood quest: Sanctuary
Dragon infusion, takes 25% less melee damage from dragons (does not save you vampires from firebreath), blades quest: dragon research
Eternal Spirit, while ethereal you recover health 25% faster (ethereal is a dragon shout that turns you invisible), greybeards quest : meditations on the words of power
Force without effort, stagger 25% less and enemies stagger 25% more, greybeards quest: meditations on the words of power
The fire within, fire breath deals 25% more damage, greybeards quest: meditations on the words of power
Gift of Gab, speech skill increase 15% faster, bards college quest`tending flames
Nightingales aegis, 25% armor bonus if you wear all nightingle armor set, thieves guild quest: trinity restored
Prolwer's profit, chance of finding more gems in chests, thieves guild quest: no stone unturned
Sailor's repose, healing spells are 10% more effective, dungeon quest: what lies beneath
Sinderion's serendipity, 25% of producing two potions instead of one when using alchemy, side quest: a return to your roots