You are not real clear in what sounds are being generated by the keyboard - so, I will assume that you are generating all the music tracks (drums, bass, pads, etc.) through a steroe out from your keyboard.
Normally, the lead vocal, the bass, the snare drum and the kick drum are all panned to the middle (12 o'clock) - and then other sounds can panned anywhere around that. Often, the most important harmony
tracks (guitars, piano, etc.) may be panned in the 10 o'clock to 2 o'clock range and then less important pad sounds may be panned anywhere from say 8-9 o'clock on one side and 3-5 o'clock on the other side. Often it is most effective to use
effects processors which allow steror outs, to pan various pad sounds in a wider stereo span and use mono outs for things such as guitar appeggios, etc. Avoid extreme panning of drums since that can sound both unatural and distracting.
There are many web sites that suggest how to mix to achieve not only an effective right to left mix - but a front to back mix (using reverb, etc.)
