Great suggestions. They could be done before the end of the year, but the roadblock is US freight companies that do not care for anything more than their own bottom line. And the feds currently are more interested in getting personal automobiles to emit more pollution that anything to do with the railroad.
Also I love smoke stops/stretch breaks but those could be shortened a bit if connections ran in a more timely manner.
This is generally true. HSR is only really needed to replace long car and plane trips, which are not that common. In daily life regional rail is much more usefull. That combined with local public transport, cycling and walking actually can replace a car. HSR alone can not. Obviously when you built a new line going for hsr is an actually good idea, as it does not cost that much more. But there is a lot of railway infrastructure around already. So adding trains on it for regional rail, electrifying it and so forth would really help. The US is probably the most obvious thanks to having a massive freight rail network, mostly without passenger trains, but a lot of countries have old unused tracks.