I've always been in the camp that Zenos dying once was the perfect amount and that he should have stayed dead. I take the OP's point about a rival, but is it the rivalry, or the knowledge that at some point we're fated to meet that challenge again? Still not gripping for me. We always win eventually.

I think what we're struggling with at the moment is a lack of wondering what is going to happen next. At the end of 7.1 and the so-called cliffhanger, my only reaction was "oh no, not her again."

Currently there isn't much that we don't understand, or at least anything that is compelling. Maybe that takes a while to build up, but despite the weaknesses of the storytelling in ARR, I was propelled forward by a desire to figure out what was going on. I haven't felt that at all in DT.