So I'm level 17. Done everything in Velen up to level 20, even a few things that were a good deal above my level. Have about ~6 contracts ranging from lvl 23-28 and one treasure hunt for level 24. I'm wrapping up the last two main quest lines in Novi now and haven't set foot on Skellige.
I feel like I'm 3/4 the way through because I've explored all of Velen save for like 6-8 spots that are well above my level. Yet I have tons of equipment schematics that are well into the 20s and even a couple that require like lvl 34. So I know I'm far far from being done with the game or story.
Character building is really weird. I've like almost 30 points in now, 5/5 Fast Attack, 4/5 Fast Attack 2, 3/3 Defense 1, some 8 or so points in Igni, Quen and Axii and then 4 points in Brewing and picked up the Sun and Stars skill. But with all that I've only scratched the first row of the character screen, save for the 2nd level Fast Attack.
Playing on Hard as well, but the challenge is really uneven at times. I'll fight some people at level 12 and they'll barely put a scratch in me, then some dude at level 9 will hit me once and take off half my health.
Menu system is abysmal. It's bad enough I have a thousand different equipment designs and alchemy recopies but my actual inventory is also full of shit and I feel like most potions and concoctions are just not worth it at all, bombs as well, and don't show any noticeable benefit when used, especially concoctions which use up all your toxicity. Oils though are good. Most food is rubbish and uneven as well. A cooked chicken leg is all but useless for health regen but then some random berry is actually quite good.
Weapons runes are also weird since I turnover weapons constantly. There's always a better weapon to be had so putting runes on them feel wasteful, but I have a ton of them, just not many duplicates of the really useful ones.
All that aside I love this game so much. The world is brilliant and vibrant, writing is spot on. It's just damn fun to play. I've really gotten into the combat and being patient. I love the Witcher contracts and hunting down monsters. I just want to go home and play more. I've even gotten a bit better a Gwent.