I don't find them underwhelming, they're kind of what I expect. Kena surprised me in a kind of - these things really do look like films now, sort of way - but Horizon and many of the other games are actually what I expect from the boost in power... what I expect from what were already very talented art teams on PS4.
I think we're at a point where character models on PS4/XBO - in some games - are insanely good already. There are improvements that can be made, of course, I'm sure we'll see them - but the fundamental high-quality in design is there today. We already have character models that are down-rezzed from insane, beautifully sculpted high definition models. The cars in Gran Turismo always look great. I think to be wowed again, its gonna take some insane, face wrinkling, nose twitching, lip spittle, sub surface scattering and crazy earlobe lighting to make something really really stand out in that department. A kind of level of investment that actually, the ROI may not be that great on - for games where you spend most of your time looking at the back of someones head.
Spiderman impresses me from a lighting perspective, weather particles etc. The fur and foliage in some of the shots from Horizon and other games are a clear improvement in fidelity, but again, kind of what I expect for a big investment in new hardware.
I can sympathise with people who aren't seeing a jump they've maybe been accustomed to in previous generations. I think I actually feel for some of the developers who had their games featured at the show, games that were maybe not graphical powerhouses - but actually looked a lot more fun than some of the cinematic games. Gameplay always > graphics for me.
Ratchet & Clank impressed me with its portal hopping mechanic. It reminded me of the multi-world hopping battle with Malekith at the end of Thor 2 or something. To have geometry from completely different scenes just instantly loading in, shattered in to view like jumping through an orange or blue gate in Portal or something - that really shows the potential in this new architecture, with this added level of RAM and disk read speed. I suspect, the things that make us appreciate next gen the most - will not be just the pretty visuals - but the things like that, which were simply not feasible before.
It makes me hope Nintendo are watching. They used to be all about the low latency, low load time, instant play experience, and I'd love to see them take a few cues for their next console, whatever that is.