The big problem (as I saw it) with the last game was the lack of things to do for backbencher, opposition MPs, and (most of all) regular voters which killed involvement. With a government potentially lasting 4 or 5 months, what are your ideas for keeping those groups invested?
I'm looking into suggestions for that, of course (a lot depends on the player base though, I don't see it being too large), but among other ideas I plan on allowing the Opposition to present legislation as well (rather than monolithic control of Parliament), running for devolved governments (if a large enough player base), entrusting players with key newspapers (with a considerable effect on public opinion or polling), or, if necessary, giving crises for people to respond and react.
Since this game is intended to run with simulated elections (and not with vote via player base), then consecuences for not acting or acting badly would be greater, thus (I think) promoting activity from the player.
One suggestion is to limit the possibility of super-majorities; if the government is having to rely on a coalitions/minorities governments then the game would be much more interesting (if not stressful for the govt)