Punk Zombie close to Toshiro gets + attack flip and they have one + build in, and Toshiro can (0) Fast him, so positioned correctly with 2/4/5 dmg (and possible Flurry) he can always score a kill, placing marker that Toshiro can use to summon Ashigaru. I have total of 4 Ashigaru for summons, they are really underrated in my opinion, very solid models, they can catch in engage and hold for two or more turns most normal models and then you can summon them again...
Problem with Izamu is that he is a killer with 3" engage and works like a magnet - your enemy usually will try to kill him asap and most likely do that as he is not so tough. From the other hand, yesterday Izamu + 2xKomainu + Sun Quiang creates an unkillable bubble in a middle of Nicodems' party