For one thing, most serious theme league players don't enjoy high caps. You can build a team with the absolute best sim players for far less than $60m, so $90m is just dumb. Tons of wasted minutes. Typically $47m to $52m are more attractive.
Also, themes typically need some sort of spice to entice a owner's mind. Just the "use anybody except no clones" isn't very different from a ho-hum typical league. Take a look at the EOL. That's a classic that has been around for more than a decade. It really makes an owner think and is pretty much a new deal every real nba season.
That's my advice. Good luck!