I'm expect SDP to make good gains in GE 2016, but only if they can keep up this momentum and not get distracted by irrelevant issues.
However I am much more interested in how WP can expand itself. I have one yardstick with which to gauge -- can WP retain its seats, win even more seats, and do those winnings make a real tangible difference to Singaporeans. If Singaporeans are better represented, and the PAP is given a black eye a bloody nose and a broken rib and is forced to change its cherish policies, then there's no way anyone can say WP is a psuedo-opposition.
A psuedo-opposition is one which only says they want to win, but never really try, and if they do by chance win, they don't work to keep their gains, and they don't work to force the PAP to change their policies.