You are obviously a "visual" person
Seeing the diagram the drums look a little "wide" but you have definitely got the concept
I think having the drums a little "tighter" would give a more natural sound
Perhaps putting the cymbals at 10 and 2 in the mix would provide enough width, bringing everything else in a little tighter in-between
I would say that from here you really are in the realms of doing what is best for the individual track
Panning is important but the stereo image you provide for the listener is much more important
Panning only deals with "left & right" - when you imagine (and visualise) your stereo image you need to think in 3 dimensions
Left & right - controlled with the pan control
Up & Down - can be a function of EQ and the natural tone of an intrument - e.g. a bass guitar will sound low in the mix, whereas a triangle will sound high - both tonally and physically
There are other more advanced tricks to create the impression of up and down but I wouldn't worry about these yet
Front & Back - Level and reverb are your friends here if you want to bring something forward or push it back in the mix
When you have recorded all of the intruments for your track I think you would be best to visualise and perhaps even draw how you want the mix to sound
Eg I want the drums coming from the middle, a guitar over there, another guitar over there, the keys coming in from over there, some bird song floating on top of the mix, a rumble sound effect down below, the vocals in the middle, a trio of backing vocalists off to the left behind the lead vocalist, a horn section standing to the right etc.
You can then try to turn your vision into a sonic spread
If a mix looks clear and uncluttered on paper there is a good chance this will translate into a good aural mix
Also, think about "making space" for instruments that are the same, or similar, registers/tones
e.g. keys and guitars need to be separated to maintain a clear and "non muddy" mix
This separation is usually achieved through giving them different positions in the mix using the pan control and also making space for each other by treating them differently with EQ
You really should try to get hold of the book I recommended - it will answer ALL of your questions and it does exactly what you are trying to produce for yourself - with clear and detailed explanations, videos and audio examples of everything
It also talks a lot about visualising the mix and drawing it out so I think this visual approach may suit you
http://www.amazon.co.uk/Mixing-Mastering-Leonard-Recording-Method/dp/1423430530/ref=sr_1_6?ie=UTF8&qid=1350597463&sr=8-6#reader_1423430530 I promise you it will be the best £16.14 you have ever spent!!!