Put everyone in the lottery with even odds. Or, make it based on record but in reverse. The 64 win contenders get the 25% chance at #1 and so on. That would make things a bit more interesting. And if you are worried that things would become unfair. Remember no team could afford to continuously sign High draft picks year in year out it they also had a lot of money in a veteran championship core. So there would be a general trickle down of talent.
I like the idea of giving everyone in the lottery even odds or significantly evening out the odds. It is unfair that certain teams (Clippers) are rewarded for their overall incompetence while teams who barely miss the playoffs only get an average pick.
Unless we get mind readers, teams will always find a way to tank without breaking the rules. I thought Pat Riley leaving the team to scout while the season was still going on was pretty blatant tanking, but lots of other people would suggest otherwise. Because really there are some GM's out there who's actions don't really make any sense, yet they're genuinely not trying to tank.