First off, those hotels kinda remind me of the Pontch, which I have heard will eventually connect via tunnel to Cobo.

I don't want to see something tall just for the sake of having something tall. Maybe a Michigan Expo Center featuring exposition of made-in-Michigan goods. Possibly some sort of Can-Am trade center. those would enhance Cobo and benefit the state. Possibly expand Cobo into either of those spaces as well.