I've always found that a second Shambling Vent rather than a Caves of Koilos works better in the long run. Shambling Vent has gotten me out of some rough spots in the past, and even helped me steal a win once.

I don't have much experience with the Raise the Alarm version, I've always ran Bitterblossom. Maybe not as much life loss makes 4 Thoughtseize safe, but I've always ran 4 Inquisitions and 2 Thoughtseizes, as Inquisition gets many of the popular threats in modern, but to each their own. All in all, your version looks solid.

Shambling Vent is fine, but I personally don't like running more than 3 tapped lands, it's pretty bad for the late game. 99% of the time I run a 2/1 mix between Vent and Windbrisk Heights, switching which I use 2 of. Lately I've been preferring Windbrisk Heights more, since drawing multiple Vents is usually bad and they often end up eating Lightning Bolts anyway, but it certainly does more to recover a bad board state.

Bitterblossom is better than Raise the Alarm, unless your specific meta is weird. If I had them I'd run a 3/3 split with Raise and cut the Secure the Wastes, though a full set of Blossom is probably correct. Thoughtseize I'm only running so many of because I lack Blossom and my meta is control/Eldrazi heavy. Running more Inquisition of Kozilek as you do is correct in most other cases though, I've found.

Thanks for the feedback!