The requirements and conjuration spell focus benefit a cleric somewhat (acid rain) but they do not have greater planar binding.
Wizards have greater planar binding and more feats, but conjuration isn't the best pick.
As for the summon going back to animal companion slot.
I honestly don't understand the reason why it has been changed in the first place.
They have always been in the animal companion slot, they just lacked scaling and naming.
The patch idea came over as fix one thing break another.
Thaumaturge had 3 problems pre patch:
1: Planar cohorts weren't scaling, your permanent level 4 fire mephit with 24 HP was useless.
At best you had an elemental which was very weak, even fully buffed.
Clerics had complete trash as well.
2: Augmented summoning didn't do anything for planars.
3: You couldn't name your planar, which devalues the identity.
After patch:
1: Planar cohorts now scale but take a summon slot.
With extended summoning the planar cohort feat is useless.
Besides summon spells are different than planar binding.
2: Augmented summoning doesn't work for planars.
3: You can't name your planar, which devalues the identity.
4: Thaumaturge sucks for clerics, the class it was meant to be for.
Solution:
1: Change planar cohort to ,cast greater planar binding.
Make it function like an animal companion.
Since it is a long term relationship you are bound to one companion.
You now have a permanent companion with name and all, which works well for both wizards and clerics.
If you for some reason need to swap it IC wise a DM can help.
If this requires too much work just change it to cast greater planar binding.
Treat it like an animal companion.
Ignore the naming/option to pick just one.
2: Augmented summoning now works for planar cohort.
3: Make greater planar binding 1 round a level, just like summon greater undead for wizards.
Last but not least, let's address the elephant in the room.
The only reason planar cohorts aren't animal companions is because of the horned devil.
It's beyond overpowered, it outshines palemasters vampire/druid animal companion until dragon pet etc.
Running around with that and a epic gate minion as wizard is just silly.
It reaches druid imbalance, and this shouldn't be there.
The other planars are more balanced and there won't be a problem with them.
The only defense I have for the horned devil is that just like a palemaster if you get caught chances are you die permanently.
It is hard to justify 'I made a contract with this devil, it's fine'.
I hope this will just get fixed, and not left like this.
It isn't working well at the moment which is a shame.
I've a hard time following the thought process behind the Thaumaturge class.
Anyway let's make Thaumaturges great again

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