While automation would be really nice, I don't think this is very high on the list of stuff that Meep needs to do, and, as staff often mention, messing with the towny plugin is hard. While there's nothing perfect to replace the first two bullet points you make, you can have no town tax and only plot tax, so residents who run out of money, while they lose their plots, don't get kicked.
You can also arrange to have a resident be vip for their period of absence, and manually pay in advance, which would be a manual version of the latter bullet points, though admittedly, more complicated.
Basically, the idea is good, but some of it is doable right now and the other stuff is, while cool, not at the top of the list of things Meep needs.