First off, Duluth, MN's Enger Tower is an awesome homage to our local area. We absolutely loved that.
There are a lot of fun elements to this tower, and each floor is varied enough to keep each floor quite fresh. I especially enjoy that this adventure features two things that the PCs (as well as the players behind them) fear greatly: birds and towers. The reveals of both of them will be hilarious when played through.
The final encounter with the "angel" is very well done and provides a serious level of chaos that I really enjoy. I hope at least one PC is compelled to jump out the window. The healing every round makes this encounter particularly brutal for the PCs.
Overall, I like this one a lot and look forward to playing it. Very nice work. Well done.