With poly graphics you can see everything and get a general idea of your next move and what to do, with fixed cameras I like the idea that there is someone creepily looking at our every move and not knowing what is next is part of the thrill. I think the tank can be still implemented with slight modification to aiming and melee/dodge with fixed camera angles to instill the uncertainty of the next beat of the game. Even the horrible tank gave a definite learning curve. I for one love every aspect of the setup in the first three games.
Whoever gets the helm to our beloved series I was just curious who likes the original game mechanics.