[eddyg]

.home, .corp and .mail are on ICANN’s “high risk” list so won’t ever be gTLDs, so they are also good (short) options.

Ref: https://www.icann.org/en/board-activities-and-meetings/mater...

[NewJazz]

They could be gTLDs in the far future, but ICANN is likely to hold off for a good long while. Better to use something that is actually reserved, though. You never know.