Fix the spellbook
I have heard that it is not possible to separate the spirit shaman’s spellbook from the druids, which is a shame, since the druid spell book just does not fit the shaman very well. And adding spells that a shaman should have would thus also add them to the druid, which needs no buffs. But at the very least the spell Eagle’s Splendor should be added for the shaman. Every other caster can buff their DC stat, even the bard. Why not the shaman? This spell is a minor buff to the druid, not big enough as argument for keeping it from the shaman.
Fix the telthor companion
The telthor is a terrible companion. It has worse stats than most of the druid’s choices. It costs a feat to even get, where the druid gets it for free. It costs another feat to bring it to full progression compared to the druids/animal domain clerics, which prevents any other multicasting other than possibly hierophant. Spells like Nature’s Avatar don’t work on it (though that might have been fixed since last I tried, maybe). You don’t get to choose what kind of companion you want, which also limits your RP. And to top it all off you can’t upgrade it to anything similar to the dragon companion in epic levels.
I suggest moving it to full companion progression. I suggest letting the player pick animal (preferably from a spirit theme, but if that’s too much work then just from the standard list). And finally I suggest letting them upgrade it to something sweet in the epics, for a shaman invested in their base class. It can still cost a feat to get, that way the Druids still win

Fix the spirit themed abilities
Chastise spirit, detect spirit, weaken spirit, warding of the spirit. None of these are particularly powerful, but the fact that few creatures on the server are considered spirits at all make these abilities almost useless. I suggest making them affect all undead, fey and outsiders as well. There are plenty more of those sorts.
Fix blood magic
The blood magic feat is the one unique thing that the shaman has that is quite powerful. 4 DC and 4 CL is nothing to sneeze at, and it’s a good compensation for the dual stat dependency for an offensive shaman. However, it costs a feat where the druid gets the same DC benefit for free from a spell (owl’s insight). It is frowned upon in RP. It is bugged when resting (dealing damage and interrupting the rest of others). It apparently does not work for epic spells (and why not, when the shadow adepts get their boost and owl’s insight clearly always works?) And most importantly it deals way too much self-inflicted damage. For a shaman just using spells to buff up, the damage is not a big deal, as they can just out-heal it eventually. But for a shaman that plays with offensive spells, it becomes a huge problem. Imagine reaching level 14 and just getting access to the spell firestorm. Now you can deal on average 49 damage in an AoE, assuming the monsters don’t save or have damage resistance. For dealing that damage the shaman takes 34.5 unresistable, unsavable, damage herself.
Even if a single spell is survivable, a caster typically unloads a whole bunch at once when say a boss battle arrives. Imagine using 6 level 9 spells in a boss battle (or another similar combination). That’s 261 damage self-inflicted damage atop of what the boss deals. It’s just silly. Compare that to the arcane bloodmage that would take 36 damage from the same sequence (though of course their version is weaker).
The solution is simply to lower the damage substantially.
Fix the AB issue
Other spellcasters that are supposed to fight with weapons get compensation for being only medium BaB. Bards get inspirations, curse song, haste and greater heroism. Clerics/FvS get too many AB boosters to list. Druids get substantial strength bonus from their wildshape and can use greater magic fang in that form. Shamans need something. I suggest sticking to the blood magic theme and adding an alternate mode to the existing feat that gives something like +4 AB at the cost of 1 self-inflicted damage for every strike. It’s not much compared to the others, but at least it would help.
Fix spirit form
5 rounds of concealment that costs a round to cast is worse than a simple displacement wand that drops everywhere. I suggest making it instantly activated.