The Gods are not as powerful as the Daedra and are unable to act as directly as the Daedra because their power was drained in order to support Mundus. If Talos ascended and achieved Godhood, he'd feel no such drain and be unlimited in action, or at least freer to act in comparison to the Aedra.
Talos mantled Lorkhan, whose flesh and heart were rended asunder, and took his place as a God. Therefore, it isnt as simple as "unlimited in action". Even the Daedra have limits (Remember the pact between Akatosh and Alessia) . Its important to contrast the works/styles of Daedra and Aedra. The Aedra are much more subtle, the Daedra are not. Whereas you demand to see proof of Talos, I have already seen it.
Know too that the Mythic Dawn sought to challenge the ways of the Gods. And look what happened to them.