Hey Mistify, just came across this and I really like your idea. I have been trying to make a shapeshifting focused class using the games current classes and have been mostly disappointed. I read through, love your idea, and have some possible solutions to everyone's "flexibility" concerns.

What if, as someone mentioned, at the beginning of the day you choose a main form. You choose the base and all the evolution allocations. You can now shift into that form at will (starting as a standard probably and getting better over time). Additionally, you have a Shifting Pool. This allows you to completely change your base form and evolutions (maybe start as a full-round, get faster over time) for a certain amount of time (1 hour per level?). Once the duration expires or you choose to leave the form, you return to your original form you prepared that morning, or to your normal humanoid form. This pool would start small, maybe one point at first. Gain an additional point every three levels perhaps? 1 at 1st, 2 at 4th, 3 at 7th, 4 at 10th, 5 at 13th, to a max of 6 at 19th. Or maybe every two levels to keep ahead of the Druid. Would have to test it to find out really.

Additionally, I liked someones idea of gaining evolution surge as a SLA. Maybe tie its uses to a mental stat. Or, make it tied to the above mentioned Shifting Pool? That might be too constricting but it might be the restriction needed to keep this in balance.

I like this idea a lot, I am going to try to flesh it out a little and then see if one my DMs will let me try it. If I do, I will report back!

P.S. I agree that it has some insane flexibility, but no more than Tier 1 and 2 classes already have. Some evolutions and the number of evolutions might need to be tweaked so we don't just completely outclass other martials, but frankly other martials need a buff anyway.