keep it simple?
I had a similar list but then I started to prioritize after I couldn't find anything reasonable. My marina does not have wifi. So I looked for cellular based systems, which work best for power loss anyway. There are no real security issues there so I focused on potential boat damage, freezing, water intrusion, power loss (which also detects if somebody takes the boat for a ride, and I can track it with marinetraffic.com). I settled on a UPS, with a water leak+power+temperature home sitter, and a cellular to phone jack gateway. It will cost me about $150+$10/month, all from Amazon and AT&T or T-mobile. I can let you know if it works well.