I've completed 3 playthroughs of DA:I (including Trespasser, but not Jaws or Descent) and have been in Velen for a couple of hours in my second attempt at a second playthrough of TW3.
Overall - I prefer DA:I. I like the 'world' - read :setting - more and the companions add something TW can't. I still can't bring myself to like Geralt, although he's much, much better than in TW2, whereas I've liked all my Inquisitors, even my Maker-bothering human male (who irritated the hell out of me initially).
The topic of "be more like the Witcher 3" though, has merit in some places. The detail level in the semi-open world regions is fantastic as is the level of ambient life. There does seem - for me at least - to be a genuine reason to go looking past that hill 'over there', which i didn't find to be true with DA:I.
The sheer volume of 'in character' things to do is mind boggling. The 'busy work' Inquisition was accused of (in some cases fairly) would have fit well with the PC being a 'blade/staff for hire' like Geralt. The little, out of the way 'complete-them-before-you-knew-about-them' quests like monster dens or finding schematics worked well, because that was exactly what one might expect Geralt to do. It is not unreasonable to expect the Herald of Andraste to do these sorts of things, either. It is unreasonable - in my opinion - to expect the Inquisitor to do them.
'Adult' content, since I've seen it come up a couple of times...the only time I actually felt like they (TW3) were doing something to titillate was when the old forest crones (can't remember their proper names) suddenly turned themselves into beautiful young naked women drinking blood. I also felt a little uncomfortable during the 'Find Junior' quest, but that content - referring to the hot tub scene - was in keeping with the characters personality, so....I was fine with it.
The issue with being more like TW3 is that would actually make no sense. Take a few elements that were lacking in Inquisition, sure. But, by and large, I would rather they refined what they had with Inquisition and made any future title more like what did work about Inquisition. More quest design like "In Your Heart Shall Burn".
Oh, and change the search function (or remove it). Completely. Interact-able items should be highlighted or not.