I think I'm going to have to side with Swordsage, unless anyone else vouches for Totemist. I like the class, and it would give me different options, but as I said, Ss offers a somewhat better build.
That said, in planning the character, I can either take the 4th level of Warshaper and gain Fast Healing 2, or I can take another Gestalt level and gain access to 9th level maneuvers. Which is going to be more useful, here? (I'd be getting fast healing at level 7, mind you, though it wouldn't scale with level- though, you can also spend a full-round action with a concentration check and heal 10 hp). On the other hand, 17th level gives me improved evasion and the 9th level maneuvers are kick-ass.
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On second though, non-swordsage levels equal count for half toward initiator levels, which would give me access to 9th level maneuvers anyway...
So, Improved Evasion or Fast Healing 2?