Pretty much. If you find yourself wanting to do sidequests, because you find some of the quest lines interesting, but want a way to filter out the garbage, its actually very simple.
All NPC's with no names have are throw away quests with no overarching storylines/impact. They are always kill X of Y, or Kill this Unique monster, they never result in fleshing out world lore, fleshing out npc's and their stories, changing the affinity web, unlocking abilities, or give the great equipment/gem rewards.
You dont have to worry about going out of your way to do those ones at all, as there are plenty of named characters with quest arcs. They arent really for experience grinding, they are more for affinity/renown grinding, which kind of sucks if you messed up and ended up in that situation, but its kind of nice they do have a way to keep the player from getting affinity screwed. This seems to be mainly implemented for trades of items (for optional sidequests of course) that at some point in the game would otherwise become un-attainable if the player didnt already collect enough of them.
You really wont need to grind much at all to beat the story side of the game, the large number of quests are for people who want to go after the optional boss metagame, which far eclipses the levels of anything you face in the story side of the game. Interestingly enough, the metagame forces you to learn how to game its combat system and fight enemies 10+ levels above the player, as the last 5 bosses are all above the players level cap. In other words, its impossible to over level for the meta game side of Xenoblade.