"felt fairly safe, with few standout features distinguishing it from their predecessors"
Outside the more avant garde stuff like folding phones and flexible screens, is that really a surprise? What more could you honestly add to a phone at this point? Even the budget end can surf the web, take an OK picture, stream a movie, and listen to music (Oh, and make the occasional phone call).
Don't take this as a negative: Since around the iPhone 4s/Galaxy S3 days, the pocket computers we all carry around have been so crammed with features, about all you can do is make the numbers bigger and faster
I'm excited to see what the next big leap forward is, but I'm glad I'm not the engineer or marketing bod that has to try to come up with what that is.