So, really, this discussion isn't about fast travel. No, it is about landscape; we just didn't realize it.
THIS!
I did mention before that it's not really fast travel that's the problem but more the game around it. Main problems there:
-Bland landscape, it just gets boring to see very quickly and if you saw one ruin of a type you saw ALL ruins of that type.
-Really nothing to do on the way, there where so few settlements and things to do and they didn't encourage you to spend much time there. If there where more small places and had more quests you'd simply be encouraged to walk the way instead of just skipping
-Annoyances, honestly the bandits, animals and monsters that kept attacking you on sight where not a challange, they where an annoyance (specially looking at you, Will-o-the-Wisps)
-Simply to spread out, Every quest sent you simply too far out no matter how minor it was. This only made walking everywhere tedious.
In the end you didn't really feel like you achieved anything by walking, it was more like you wasted time on it. Simply fix those problems, have a landscape that's interesting to view, put more settlements between towns and have them contain more (possible random) quests you CAN do, make the main road safer so you don't get jumped by something every 20 steps and have more "regional" quests.
With that you CAN have Oblivions fast travel system without a problem, it would simply be a shortcut but using it you'd just miss all the stuff that's in between the travl point.