You both are downplaying drought. The ability to setup weather with such a small cost is huge. Setting up the sun that way means not only don't you have to "sack" the pokemon for your weather, you can reuse him easier, you have guarntueed weather, you can put more pressure on your opponent , ... . Then don't forget what it does to some pokemon. Charizard becomes a huge monster under the sun. Under solar power it has more special attack then its mega. This makes charizard a threathening sweeper. Chlorophyl users like leafeon get monstrous speed, moonlight and synthesis get their healing increased, ... .
To refer another fangame, in desolation, you get ninetales. When you as a sun team get draught, your effiency improves by a lot. I clearly noticed the difference. It is not a threathening sweeper but it is a dangerous support. It boosts my heliolisks special attack, it makes a setup clefable easier, it makes charizard a nuke, ... .