Of all the sets to do a sequel to, Innistrad? Really!?
Curious what you didn't like about Innistrad. The general consensus, at least as far as I was aware, is that it's one of the best recent sets from pretty much every angle. Folks loved the lore and mechanics, regarded as top tier as a limited format, and it provided a bunch of sweet format spanning constructed cards.
Unless you meant Innistrad as a block, then I would understand since Dark Ascension and Avacyn Restored had some missteps.
We hang out in very different circles then, because as far as I was aware, the consensus was that it was just above Kamigawa in terms of quality of modern sets. (Fitting as it fit the same niche of modern sets as the awful set that came between the best set (Mirrodin) and the second best set (Ravnica))
Honestly, I never went for the Gothic horror/Universal monster aesthetic.
The mechanics it used were all either boring, or terrible. (I'm looking at you Transform, anything that requires proxies and keeping track of cards outside of your deck is a failure.
Fight was just giving a name to something that had been hovering around, but I'm glad it was standardized.
Vampires getting stronger when they hit players was solid but boring.
Morbid was always kind of a boring trigger compared to "Whenever a creature dies".
Flashback could never balance itself properly in terms of cost, plus fuck snapcaster.
The fact that something as boring as Innistrad was followed up by sets as terrible as Dark Ascension and Avacyn returned ultimately doomed it as one of the worst blocks.
If you want a good "Functional but kind of dull" set with a moderate focus on multi-colors, there's Theros.