I'm running a FF/Ice Defender and have my team mates jumping into the centre of mobs killing things like crazy. They almost never get hit and I just turned level 22. My first 50 was an Ill/FF controller years ago and I think to this days FF is a better secondary in many cases but so far the teams/TF's we've done have had people saying wow I almost didn't take any dmg. Primarily that was Due to FF, and it's basically easy mode. IO's should make the set Shine (easy to slot LOTG) and lots of ice storm/Blizzards in relative safety to come.
Don't worry about what "could be better" just enjoy what you've got. Lately I've been trying to find combo's I never see, like Ice control/Poison etc..