I've gotten to the point where I have several now much lower level contracts on my tracking list from when I first accepted them. From completing a few of them I found out I get next to nothing out of them experience-wise, so I really don't want to waste my time with them. It looks like I'm not able to purge those contracts - at least I haven't found a way to do so - so they're stuck on that list. =/

Given that, I'm afraid to pick up any extra quest board contracts right now since I have no idea what their level criteria might be.

Not sure if it is possible, but what the point to play this game if you ''waste'' time with lower xp contracts?

If you want them out of you quest list, just do them. They will be so incredibly easy that 'time' doesn't come into it: there's fast travel.

Quests you pick up stay in your log until you do them. Once done, they are moved to the completed log.

If all you are after is to have a "clean" quest list - just do those low level quests because they will be easy and fast. You will get something for them besides XP.