I've played one game with my proxy crew and my husband has played two. So far the main things I've noted about the crew in general is that they have really good synergy together.
The Soul Porter was definately worth the 2 pts as I used his push ability (sorry doing this from memory) every turn since the crew is so slow. I also used him to cast Yan's healing spell as well.
Chiaki is good for her heal each activation, but the model has to be within 2". But that's another thing about the crew-for a lot of the really cool stuff to work, they need to stay close together. She also has her cleanse spirits ability which is going to allow you to get rid of poison, paralyzed, slow, etc. So worth it!!
The boys (izamu and Toshiro) are good together as well as one of them has a buff for models within 4" (again doing this from memory) that I used for the others melee that made him a beast. Add that to izamu being object 2 (hardly anything hits) and Toshiro HTW 2, and they're around awhile.
The Ashigaru were a little more iffy. I liked them but only if they're close enough to get the buffs they need from the ancestors. And if they die make sure it's within range of Toshiro so he gets his conflict tokens to bring them or PZ's back.
In my game I didn't use Yan for much more than support but I can see some good potential from him. His ranged spell is cool, he can heal and he gets more awesome as stuff happens in the game and as you go up the paths. I liked boosting his defense and then damage in the game we played, but it was a "killy" scenario.
I look forward to playing him more and maybe trying other models as well. I'll probably keep playing him as a Resser as well.
Hope you have fun with him!