This subject has been discussed over and over again. It is on the top 10 list for sure, Lol. It has been dropping down though, as these days, everything has an internal antenna. In the early days, everything had a connector on it, coax was always laying everywhere. Your shop, service vehicle, closets........you name it and it was infested with black snakes, LMAO.
You will find that the older you get, the more attractive mounting the antennas at the top and the radio on the bottom becomes. This is especially true if the repair problem is taking place at 3AM in February.
As mentioned by the others, it has it's pros and cons. Along with the extra expense of the coax, waterproofing, proper grounding and your tower becoming a thief magnet, you also have to consider how you will attach the coax to the tower. While this is a minor issue for the most part, it is a subject with lots of opinions.
Always keep in mind that whenever you add something to a home install, tower, etc. It is one more point of failure that could make your life suck. Each connection is one more place you will have to look at in the event of a failure. The more points of failure, the longer it takes to rectify an issue when it occurs.
If you luck is anything like mine, then once you get the call for an issue, the problem will still be at the top, even WITH all the important stuff at the base. Good luck with whatever route you take. --