Are there plenty of areas to fish with a 22ft bay style boat? Seems like I see a lot of flat bottom boats in the pictures, so is the water mostly shallow? Sorry, I've never been there.

You can go out and find deeper water easily. I do a lot of fishing in 6-8 ft water during certain parts of the year

Yes

Stay in the channel until it ends. You should have plenty of water. Especially with the high tides.