Once I hit level 5 or so, things became a lot less interesting.
Hmm... that must have come pretty quick then. Leave Vault 101 -> level 2. Clear out Springvale School -> level 3. Enter Megaton, do first chapter of Moira's quests -> level 4.
I used a mod that cut combat XP way back and increased the amount of XP required for each subsequent level. It actually took a decent amount of time to hit level 5.
I can't imagine anyone playing this game without an XP mod to slow leveling.
I still found levels 5-10 interesting enough, but I found I tended to grow board after level 10. That's what happens your character is a walking god.
Fo3 may have been easy once you level up.. but if it werent for the wikia calling out where everything is, i would imagine peoples opinions might be a bit different..
For me the game wasnt as much about killing everything, but more about the exploration of it all.