Tanking is a bad option, how many teams did that and had success? 
Seattle/OKC most recently, and they never had to win the lottery to do it. They scrapped a solid playoff squad by shipping out their expensive vets like Lewis and Allen, and built a young core from the #2, #4, #24, and #3 picks over a 3 year period.
By Year 5 they'd made the Finals and are in a good position to contend for the next several, despite not having nearly as good of a financial situation as we do.
There's no denying the Thunder have enjoyed some pretty incredible luck to reach that point, though. It's not really a method that you can expect to duplicate exactly.
If the Rockets get Howard this summer you could argue they are in nearly as good a position as the Thunder are now, and they never had to all-out tank in order to reach that point.
Of course, the Rockets also benefit from having one of the best two or three GMs in the league who finds great value in the draft nearly every year.
I think the key point is that rebuilding into a contender requires a lot of assets to do. The primary thing that seems to be required for getting such assets is being really opportunistic and following a disciplined plan to do it. There's more than one way to acquire assets, though. Luck, as always, is a big part of it. But then, good GMs tend to make their own luck.