Great points. I love the idea for micro-generation of power based on the expansion and contraction of your own house. In my case, I hate to say, it would take a LOT of caulk to seal up my house to anywhere near tight enough to make it feasible.
One thing I like about the tidal power is, as you mention, the tugging of the moon that makes it happen. Other than solar power, it may be the only external source of energy, available to our world. IMHO, the only feasible power source is an external power source. Otherwise, we'll just run out of whatever it is we're using. But, as you say, there are MANY ways to capture the power of the sun, for example. PV isn't the only way. Leveraging expansion and contraction is possible, etc.