i doubt PLAN intend to use the base when it is ready, they are like buying a parking spot first in case they need to move a taskforce there in future conflict, i see it as preparation work; depolying a standing force like is US is too political and wasteful. China main maritime interest is still in the pacific.
"It doesn't have to be a political party supporting re-unification with China."
how can you 're-unification' when you never was 'part of' in the 1st place? the only country singapore might unified with is Brunei (already allied) or Malaysia (if their racial policy changes to a more moderate ones). Singapore might be heavily chinese populated but the mindset is quite difference, while not fiecely independent at all, the people are used to racial and religious equality; and i dare say they have the highest level of that as unlike other state with minority, the minority here learn and spoke their own language, preserve their culture and religion. school even offer chances for some student to learn languages of other races. it is not uncommon to hear the local mix different languages into their convesation; english is prefered as it is the business language. TV culture also makes Singapore close to US culture (and japan pop culture). the reason why no party suggestion 're-unification' with China is because it is not a popular idea at all..