The quests were designed with it in mind. You could either walk half the game world every time or use fast travel.
As a consequence of the levelling problem, not using fast travel also meant having to accept that by lvl 15 all travelling NPC's would be dead.
Optional is when there are real options.
then fast travel isnt really the problem accordin to wht ur sayin. its about the lvling issue (which has been said to be resolved) and the quest location, so instead of havin quest all over the place why not mak the quest relevant to the city/quest giver.