Freeze water is an air spell, which is available quicker than windwalking. But water or wind walking is better than having to cast the freezing.
I can absolutely confirm the azracs are disadvantaged - well, I am in the game I am playing with Sprout. Gold being tight, it's a big chunk out of it to build a builder, shipyard, then a transport. This at least gets you off, then the serpents get the transport. Even a ds would get splatted. Maybe you could cast fm on one and whip it away from the serpents, but fmds are frowned upon in many quarters.
You could have a tower giving water walking to all, but then that defeats the object of having the geography as it is. So I'm still thinking the only way of doing it is to have the same spheres available to all.
I don't suppose you can add to your spheres like you can in the campaign? That would be neat. You could have three to start with, then get given 4 on, say, Day 3 so you know what you are facing then choose water if you are astute enough and need to.
My thoughts so far, TT. Keep up the good work!