My main issue with Dark Souls 3 is that it is the only Soulsborne game which doesn't really stand alone, to my eyes. It relies on the existence of the other games in every way and doesn't have anything to say which the other games haven't already said. It's leans on recycled lore, assets, areas, NPCs and as much as I enjoyed a nippier Souls after Bloodborne, there is a real lack of build variety compared to the first two games. It's kind of like a greatest hits album. It might be all killer but it has no inherent character of its own.
I've played through it I don't know how many times but the best playthroughs were on the Japanese version because I imagined so much fantastic lore and reasons for various links with the other games. It turned out it was little more than 'hey, remember this?'
It's gorgeous, the combat is very fluid (especially on the Pro), there are some fantastic areas but I can't remember anything about the base game which wasn't indebted to the rest of the series in some way, or weirdly (lazily) explicit in its references to Berserk, the manga. Having recently read all of Berserk, it actually made me think even less of DS3 (and Bloodborne, for that matter) because so so much visual design was simply copied from it, rather than used (mostly) as a springboard for inspiration, as with Demon's and the first Dark Souls.
DS2 gets a lot of flak but it dares to completely break away from the world of DS1 (and, visually, from Berserk) and it's probably the most varied and unusual in the series for that reason. Its themes are moving and it has a cohesive, direct message, and it feels perfectly standalone. Dark Souls is the best but I would more likely go to the barricades for DS2.