For some cases, you can: If you have a large directional antenna, it might, from very far away, simply look like a beam-generating "flashlight" for radio waves. That breaks down very quickly if the wavelengths are not much, much smaller than all physical objects interacting with them.
We even use specific terms: If wavelengths are very small compared to all objects they meet and a few simple "macroscopic" formulas can describe their behaviour, we speak of optical (ray) propagation. When dealing with RF, we don't; RF doesn't behave like light, and thus, the usefulness of the analogy doesn't exist. So, no, we can't be "much simpler mathematically", because the easier model of what you know as light propagation simply doesn't work¹.
For most cases, you can't compare antennas to light sources.
First of all, the analogy with light sources doesn't work out fully: Your flashlight works with DC coming from a battery. Your waves coming out have frequencies beyond 10¹⁵ Hz. In an antenna, the method of generating the wave relies on the current going into the antenna already having the frequency to be emitted, and the antenna just acting as an impedance matching component between wave conductor and free space.
Then, the wave emitted from an antenna has some sort of wave front, which implies coherent phase! Your LED or light bulb doesn't have that, at all.
So, the light beam from a torch is simply physically very different from the beam from an antenna.
¹ Things are way more complicated for light than you think once you look very closely; a beam is not beam.