|Pathfinder Adventure Path, Modules Subscriber||
After building and testing some shamans and reading the suggestions posted here, here are my two bits on the topic:
Armor - Light (maybe add a hex to a spirit that grants medium)
Weapons - Simple (maybe add a hex to a spirit that grants marital or some exotic weapons)
BAB - 1/2
Saves - Good Fort, Good Will
Spell List - I like the druid spell list as a basis. The augmentation to this list based off of the spirits expands it in the appropriately thematic direction.
Casting Type - A prepared spontaneous (charisma) caster based off the druid list would make for an interesting, dynamic, and different character when augmented with the spells provided by the spirits. The spells available each day would be chosen from the druid list at preparation, but the spells per day could be used to cast any of them spontaneously. The number of spells available each day could be 2 per class level, no spell level limitations (A level 5 shaman would have 10 spells they could prepare. They could select, for example, 4 level 1, 5 level 2, and 1 level 3, or 3 level 1, 3 level 2, and 4 level 3). The spells per day would be low, similar to the witch, with bonus spells from a high attribute.
Spirit Magic - Add 2 to the shaman's spells per day for each level they can cast. The spirits also provide spells of their own according to each spirit to the shaman's prepared spells each day. Some additional spirits would probably need to be created to add the desired cleric spells to the list.
Familiar - Keep the familiar, it serves as the vessel for the spirits.
Wandering Spirits - This is a fantastic mechanic, but it should probably be accessed earlier (a low-level shaman is pretty awful at the moment). I would prefer to see all spirits be wandering, with a new spirit gained every 3 levels (1, 4, 7, 10, 13, 16, 19). The Shaman selects his spirits at the beginning of their daily preparation.
Spirits - Change the spirit abilities into hexes and remove that particular aspect. Greater Spirit Ability could be turned into a Major Hex. True Spirit abilities are turned into Grand Hexes.
Hexes - Each day, at the same time spells are prepared, the shaman can select the hexes available to them They may select 1 hex for each spirit, but need not select a hex from every spirit. The Extra Hex feat allows an additional hex to be selected. A Shaman gains a hex every other level beginning at level 2. Many of the witch's hexes could be added to various spirits.
Major Hexes - at 10th level the major hexes for each spirit are available to be selected.
Grand Hex - at 18th level the grand hexes for each spirit are available to be selected.
Many of the hexes and current spirit abilities need a bit of work to make them balanced or useful. There are many of them which will currently never be selected since they are either completely overshadowed or not worth the limited resource slot.