Cheers for the advice guys, so in summary either get a massive blade or don't bother and wait for a proper windy day when it's safer.
I did get a new kite in the end though, I've now got an ozone frenzy 7.5 which I picked up cheap to practice boarding and depower instead. Gotta say I love the depower system, though flying with a bar takes a little bit of getting used to after handles.