I think if I were trying to launch an Urban Fantasy RPG product line, the first thing I’d do is figure out a cool core idea. For all its flaws, WoD latched on to cool horror/fantasy concepts with inherent fan bases- vampires, werewolves, mages, mummies, etc.- and made their own take on them. And it was good enough that they hooked a sizeable audience.
OTOH, the CoC environment is centered on one of the major beloved genre fiction settings there is.
So, you’d have to find your hook.
Then, if you want sustainability beyond selling a core ruleset, I’d use a RIFTS- like approach to releases. That game has innumerable supplements, but few of them are modules or adventure paths- they’re more akin to 2Ed D&D’s box sets detailing regions. But I wouldn’t do continents, regions or states, I’d strictly limit myself to detailing cities…real or fictional.
With the former, there’s a wealth of information to grab already out there- maps, local legends & lore, culture, cuisine…
With the latter, you make it up, of course.
A well-done sourcebook on a major modern city could host entire campaigns, and provide fodder for all kinds of crossovers.
Oh, some more IP to mine:
Big Trouble In Little China
Gremlins
SERRAted Edge books
Secret History novels
Nightside series
The Prophesy
The Fades
What We Do In The Shadows