While always liked larger screen phones (even back when they were called phablets), I do wish we had more choice (and competition) in our smartphone products. But I guess the impact of economies of scale and platform network effects is so large that we can't really have effective competition.
I wish that together with the ever increasing physical size we saw more development in terms of screen resolution as well. Sure, we've seen improvements in brightness and refresh rate, but still even many of the 6.7" screens are only 1080p. I think when looking from this close, anything 5+ inches should be more than 1080p; maybe 2160p is a bit too much, but 1440p is a happy medium.