Well, in our case, even if you spend a lot of money, you are not sure to know the top 5 of the draft. It's a question of luck then. So I don't think we should add a lottery.
Well, theoretically speaking having a lottery should decrease the incentive to throw games, since having the poorest record doesn't guarantee you the top spot.
On the other hand, the gap in talent between the top players in BB drafts is less than in an actual NBA draft, so it's not really fair to compare the two.
"I don't know half of you half as well as I should like; and I like less than half of you half as well as you deserve."