[@Divinity]
Perhaps, but any control gained would be vastly inferior to a being whom's main power is to control the electromagnetic spectrum, which also includes all spectrums of light.

[@Savato]
I'll admit Black- and Whitebeard are more powerful than Enel, but there are still very few characters that can match his Island-level feat.

His level of awareness comes purely from possessing ridiculously powerful Observation Haki, there's no indication that this is reliant in any way on his Devil Fruit. His Haki is just that strong. Which indicates that if he became aware of the other types of Haki, he would be able to learn them quite quick, making him a deadly opponent to face.

And without his rubber immunity, Fourth Gear would get annihilated by the sheer damage output of Enel's attacks. This is beyond merely annihilating mountains, this is island-busting. Without Luffy's immunity, he would have been fried to a casual crisp by Enel's first attack.

Even without knowing about Haki Enel could annihilate most enemies in the New World. A single El-Thor or God's Judgement and they're gone. And it's not like they're going to get the drop on him, when he can sense them coming from hundreds of kilometers away.