I'd stick a set of Wellgo MG1 pedals, a Charge Spoon, a cheap slightly shorter stem and a set of nevegals and a set of Lizard Skins Charge grips on it and call it good. Should be about £100 there. But really, it's a pretty damn fine bike as it is and doesn't need upgrading in a hurry. You're not going to upgrade on the wheels for £100, that's for sure, 317s are good rims. But contact points are personal taste.