the silence said:
"Not finding anything to do".
I'm pretty much constantly questing and I have already overleveled Main and "big" side quests in the area I operate.
It's just not possible, if you search.
Has to be a bug. I think nobody should be lvl 4 in Novigrad if he didn't go straight there before doing any Velen quests.
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About the people talking about sets: I'm mostly using griffin gear, but I constantly find stuff that's better than the set.
Is it just the griffin set?
The upgraded gear is the green Witcher sets, there are 3 main sets in the game that can each be upgraded 3 times. Griffen, medium armor which is sign intensity based, Cat, light armor which is attack power based, and Bear, heavy armor that is critical hit based.
Each set has a set of swords that play off similar stats, and Cat and Bear also have crossbow schematics. They all have 3 upgrade levels: enhanced, Superior, and mastercrafted. I don't know what better armor you are finding or what level you are, but the mastercrafted witcher sets can compete with any end-game armor, and the similar stats make them appealing for stacking ridiculously high bonuses. You should at least keep the witcher set with the bonus you like the most in your inventory as it requires the previous level gear to upgrade to the next level.
As for the exp bug, haven't been hit with it yet, but if you are playing on PC, you can unlock the devconsole to give yourself a few free levels, especially for situations like that poster up there saying he's in Novigrad at level 4. Really, just completing the main quests in Velen should get you to the 8-10 range, and the starting quests in Novigrad should bump you up to 15-16 pretty fast, I hit 20 (with about 30k gold) before I even left for Skillege, and ended up way overleveled for the starting quests in that area.
That does bring up a valid issue with the game, in that the monster levels are all over the place, while it can be cool to run into a really strong ? level enemy or area in Velen and make a note to come back, it often seems random at best, with level 25 griffens hanging out right next to level 8 wraiths, or a level 23 fiend guarding a treasure 10 feet away from some level 5 drowners guarding a different treasure. While I'm not a fan of level scaling, neither do I really like having to dodge a bunch of high level enemies just hanging out near the exit to a cave I just explored for a lvl 6 main story mission.
It gets annoying in the opposite direction too. For the first few hours in Skellige when the level recommendation to go on the boat to get there is like level 16, but a lot of the enemies and quests getting off the boat are 4-5 levels lower than that. Since I came to skellige at around lvl 20, I ended up with a bunch of grey quests that gave no experience and no useful items at all.
But otherwise, I was never hurting for content, my quest log always had at least a half dozen contracts or secondary quests that were right around my level, and other than a few wonky areas in Velen, the monsters in the Novigrad region seemed to have a much smoother level curve.