I agree with PhuzzY LogiK that now player should have some influence on his creatures position, especially because it also affects which creatures attack first (important when you have antimattered creatures, feral bond, opponent has a bone wall etc.)
Also if in your middle row there are less than 7 creatures (eg. one was killed) but you have creature in top or bottom row, you should be able to move it to middle row. Also after you make a creature immortal you should be able to move it to top or bottom row to make space for non-immortal creatures.
Unless it is Zanz's intention that you cannot move your creatures, not a 'not yet implemented feature', then it would also make sense, though I would prefer being able to move.
I dont think this will ever be implemented, and I personally wouldnt like it if it was anyways. Other card games make you have to think about if you want to put a creature down because the space is limited (some only allow 5 creatures) this one lets you have nearly unlimited amount, so unless you are worried that they have a rof, then you can just put it down, and if you dont care abotu the creature, you can just put it down. But now, even the creatures you dont care about, you will think tice about putting down because you might need the space if the opponent has a flood. Adds more strategy, I like that you never know what you have to prepare for.
Also, I would hate to have to choose where to put my monsters at each turn, it makes the battles go quicker. You cant make your creatures stop attacking when thiers a fire shield, so why should you be able to move them away from, or to the flood?