Regarding selection of alternates, I think the availability of train services from one airport to another should be quite low on the list of desirable qualities. True, it might be seen as a plus point to get home as soon and as cheaply as possible, but the term, "pressonitis" seems to be a factor in a significant number of accident and incident reports.
No, that's the reason why the "availability of train services", and other factors relevant to the purpose of the flight, should be high on the list of desirable qualities. The way to avoid "pressonitis" is not to assume that you have superhuman willpower, but to create contingency plans that make it easier to take the right decision when it is required.
When the decision to divert sits on the margin, you'll make a better decision knowing that your diversion has a train connection to that business meeting you were going to, or perhaps a scheduled flight home to your bed, rather than requiring a night spent sleeping in the aircraft.