I'm in a similar way, just having my first winter. One thing that I do every once in a while is put a little bleach in the sump pump to discourage funky growing stuff in the line that could back up the line.
On another subject, I'm worried about what happens if my little sump ever fails (I have a furnace humidifier too that dumps into it all winter). I'm thinking of putting the existing sump into a 6" high plastic tub and putting a cheapo bilge pump style sump next to in in the pan/tub so that if the first one failed it would overflow into the tub and trigger a float switch on the backup, which would save me from a wet basement. I wouldn't worry about any batter b/u because the furnace and humidifier wouldn't come on and dump water if I didn't have power. Or, maybe I get a water detector alarm thingy. That would help against washing machine hoses busting too. Anyone know what the cheapest way to do this is?