My confidence on the housing development proceeding without substantial modification is maybe... 60%. On the one hand, PlazaCorp is usually pretty reliable about following-through with things that they make public, and they usually only take on one big project at a time. They did The Exchange, then the Hilton Garden Inn, and now...potentially this. This shows focus and intention. The exception to that rule might be whatever is happening (or, more accurately, not happening) at the old Gibson Guitar factory. But a Hard Rock Hotel / enterprise center / museum in the Northside is a
very different prospect from some badly-needed apartment units downtown. Plus, the city has wanted denser housing developed on these blocks for years, so they will generally be supportive in the process. And as mentioned previously, virtually zero nearby residents to complain about height, shadows, traffic, or any other NIMBY nuisances.
On the other hand, securing funding for projects like this has gotten harder and harder as of late, and material escalation and labor shortages are still real concerns. Several other big projects proposed around Kalamazoo in recent years have either been cancelled or gone cold. The 10-story proposal on South Burdick St. comes to mind, as well as the stagnant attempts to develop the surface lot at
S. Edwards St. and Bates Alley. No doubt the pandemic killed some projects. But the market is still very unpredictable right now. If anything changes / kills this proposal, I don't think it will be a lack of demand or the visual impact. It will be the funding.
For what it's worth, I don't think I've seen or heard anything that indicated both would necessarily be built simultaneously. It might be a Phase 1 / Phase 2 kind of thing. So maybe they build the shorter, less expensive one first, see how it does, and then adjust the height as necessary for the second one, depending on the outcome.
I'm much less confident about the multi-purpose event center / arena. I'd give it 10-15% confidence rating, max. I don't understand who would use it. From what I've read, neither the Kalamazoo Wings nor WMU's hockey team have any interest in using the space, having invested millions in their own venues. And the County already has the Expo Center. Granted, it is not centrally-located and certainly not a landmark piece of architecture, but it is functional and heavily utilized. I haven't seen any real proposal, or even a sketch, put out in years for a downtown arena. No one has explained how the parking and traffic would work. I actually feel the opposite way: with each new development on the west side of downtown, it seems increasingly unlikely that an arena / event center (with its inherently large footprint) would be built. There are just so many other more pertinent needs (housing, housing, housing). And I don't know of anyone in the general public that honestly supports the idea, apart from employees at Southwest Michigan First, some county officials, and maybe the nearby hotel owners / operators.
Disclaimer: I'm forming all of these opinions with zero insider information. But since you asked.