Draft is so overrated. Even with the first pick you can get very average prospect, which is worth not more than 100k in the market. Of course, it is possible to get 18 years old GOAT with 60+ TSP (total skill points), but it is so risky gamble with such a low probability. But some managers just like to do that. Take that gamble, go for the best pick and expect to get good draftie.
But I think, it is always better to win. Go to next division and get more money. And with money, you do not need to take a gamble in the draft. You can just buy any prospect you want in the market. :) Or, just buy finished product and skip all these years of training.
256 teams will promote to next league this season. It means, almost 4 teams from every league on average. So the best time to go for the win is right now. It will be much more difficult to promote in the future. So you are absolutely right, higher league = more money.