Obviously I am not an economist, so I know zero about corporate finance, but do we really need to complicate the tax issue as our present tax laws have become?

Obviously I am not an economist, so I know zero about corporate finance, but do we really need to complicate the tax issue as our present tax laws have become? (I once handled accounts payable for a local government entity - I quickly transferred to an IT position so that's all I know beyond balancing my own budget) Why won't a more simple approach be workable? I favor a tax based on percentage of gain. If a Mega-Corp makes $30Bn a year, and I only make $30K, we each pay accordingly, at the same percentage rate. Of course there would be a great debate about exactly what that percentage should be, but it should be equitable and not too onerous. Why not hold corporate entities to the same standard as individuals? Isn't the USA supposed to be about equality? (Remember, freedom & equal rights for all?)