My issue tends to be the exact opposite. Just unlocked the achievement for finding 125 locations the other night, and have not picked up the Explorer perk. It was the same thing with me in FO3...I would start a quest, have to go 500 yds. East to get to said locations, and I would unlock 10 locations on the way, cause I wander all over the place.
So no, one of my favorite things to do in this game is just wander and explore and see what I come across.
Yep, I'll usually pick a ^ type tick on the 'radar' and just head towards it.. often no-where near the same direction as any quests i have would lead me to.
The only annoyance i've been running into, has been the lack of accessible buildings at place..
'you have found SO/SO's Gas Station.. +10 XP' ...
Great.. but the only thing there is a suitcase with one mutfruit inside... WHOOP DE DOOOO!.
Or some buildings where (if they're not boarded up), you go in and there is a 2nd floor that you can see due to a hole in the ceiling. but no way up there, and MAYBE 3 giant ants... wheee.
If you're going to put something as a marker.. at least make SOME reason to be there.. more than the ability to gain 30xp if you're lucky. Same goes for the caves.
While I'm not expecting a huge dungeon. More than 1-3 rooms would be nice