On the topic of Sphere Magus, Sphere's of Power is actually a surprisingly popular subsystem, especially here on the forums, that said, I wouldn't suggest adding it to your guide. While it plays similarly to the core magus, the change in casting would make it a larger project than you should take up.

If you decide to add it in on your own accord, I suggest linking to Stacks handbook The Orrery and note that most of the information you have is still valid, except for metamagic feats being much less viable for the Magus, due to spontaneous style casting time increases.