We don't have any permanent tie downs; we use the rubber shelf liners like this stuff:
http://www.amazon.com/Con-Tact-Premi...13B5624E41AE41
In addition to being really sticky to keep things from sliding around, it also is a little "foamy". Putting some between the plates protects the plates and reduces noise from them rattling around.
Our version of "local internet" on the road is simple: a shared plan with a high data cap. Since we have many mobile devices with most having LTE it seems pretty simple. As for putting stuff on the TV I do have a chromecast hooked to the main TV which doesn't get used much. Typically the only thing on our TV is my son's PS4--we're camping so we are outside most of the time anyway.