When using spirits, it seems to me that most of GMs...and PCs also, think of them as of a combat drone or something like that. IMO spirit powers are described as "inspiration" not as exact statement, and GMs are encouraged to modify them to their own taste. It takes a little prepatration of the scene, and planning of using indirect powers and skills, but f.6 Toxic spirit is more than just melee oponent. With such powers as Desire reflection, used on the whole team, it should be nice to see them fight each other...Im not going to spoill more, I have a PbP on hold where Id like to use this tactics to see the result. Also, in that case, Ive entered scene quite straight, well on the other side, such meeting may be a very dramatic and gameplay with horrorr atmosphere.
Proper challenge also may be built by not revealing whole oposing force at first combat turn, making the scene graduating a bit.
And...to quote kontact, every piece of land in most cities is tainted by background count. This should give game good balance, at least drive for cleansing on the Mage side.
I`ve witnessed a game that was won by mage using just manipulating spells..even on his own teammates. Thats much worse than +4IP.
Lucky for us, GMs, we may use astral signatures for tracking the mage down, using pieces of his victims for ritual spellcasting on him.
Also...not exactly RAW IMO...but in awakened world with talisleggers a lot of people would have some fetichs or something to protect themselves from magic. may or may it not work for mundane, that is up to GM if he wants to create such things providing counterspell or other protection for possible magical threats...