1. Every team in the lottery has the same odds of getting the top picks.
The first thing the NBA needs to do to restore competitive balance is to eliminate the likelihood that the worst teams in the NBA get the best odds at higher draft picks. If it's this easy for bad teams to tank and destroy their fanbase's desire to watch the games, then it's time to take away the concept entirely. If you're a good team who went 41-41 but missed the playoffs, you should be rewarded for your competitive mentality. Not punished for it.
Teams in the NBA are only ever bad because the coaches and executives allow them to be. If they were forced to put a competitive product on the floor, lest they lose revenue, you'd see a lot more parity. The problem is there's a cheat code to get the best rookies and teams exploit it. Take care of that problem. Get rid of the cheat code and make teams regret not putting a competitive product out there.
If your only goal for success is to suck, draft the best player available, and then build around him, you aren't actually good at your job. If you have to actually scout, draft, sign, and trade for guys who can make your entire team better, you're not only going to prove to be a good GM but you'll have a team that's more competitive year in and year out.