beware just adding a whole load more sugar, especially simple refined sugar like granulated. Unless you know how to do an attenuation limit test you wont know how much potential fermentaion is left in the wort, so might be making glass schrapnel bombs.
If you want more flavour then add an oz or 2 of pellet hops to the fermentation once its down to 1010′ and has been cooled to 9 – 8 ‘C . Leave these for a week to steep prior to bottling .
Depending on what you want to produce you could use summit or cascade for fruityness. Topaz would give exotic fruits like passion fruit or kiwi flavours. Bavaria Mandariana should give an orangy like finish .
Ze Germans would probably add Saaz, Premiant, Tettnang or Hersbrucker.
Going mad with American fruity hops will turn your Lager into a IPA or Hop Bomb beer like Torpedo if you go abit mad and the subtle malt flavours will be overwhelmed