Well, if one would ask what I enjoyed so far, answer would be "Pretty much everything!" XD But, as a new player, the only Star event - Solano one - was pretty much impossible for me to participate, so without even a token unreduced & unskilled featured unit I was able to scrape up from previous Farm event to unlock the scene of, my view on Star events were soured somewhat). On the other hand, this hard and heart-wrenching decision to skip the event (and I really wanted her!) allowed me to level up somewhat, while these back-to-back events do well to slow my progress overall... And I'll surely learn to appreciate the ability to get a perfect version of a unit more quickly and with less praying to Random Number Goddess later when my team would be at least somewhat comparable to that of veteran players. Anyway, from the position of fledgling player, breaks or even better, 1.5x normal drop "events" would be greatly appreciated. As well as reruns (and I mean reruns as it were) as well, like I wrote in my previous posts.
Then wat I'd like to see more of? Free Sacred Crystals, of course! XD On a more serious note, another Drill with useful Silvers (maybe ones of advanced classes) and Gold Princess as a clear reward would be good. Challenging, but always there for you to try your hand at later with better team if you can't do it at the moment. And Princess is only "basic" class we new players don't have a guaranteed access to. Well, no gold Valkyrie either, but Princess would be a better helper for a neophyte, I think. More lore and main story maps are all already mentioned.

An on the matter of missing units being replaced with Nutaku exclusives: I strongly disagree. First, this would more or less seal their originals' fate as something we'd never see, ever. And I, and many others, really want not just units, but these characters (types ;oP) specifically. And second, and even more importantly, I frankly have less than zero confidence in Nutaku artists to make the new units consistent with overall game's style. And having characters sticking like a sore thumb would only serve as constant reminder of the waifus that were supposed to be there, but whom we'll never be able to love and cherish.
I am rather partial to the idea of exclusives in principle. It would be better for every players to be able to experience everything game has to offer no matter the platform they play at.