I don't think I would trade a proven NBA commodity like Sam Hauser for a draft pick we don't know if he will pan out.
I also think 40 could get us someone of value.
The premise is that if you were able to trade Hauser for #21, you would end up with about $10M more in room under the tax. You could then have that much more to spend on a free agent to hopefully get a better FA, or you sign another FA. Right now, BOS can spend say $15M on a FA, trade Hauser and you could spend $20M or more on a FA and still be under the tax. Plus you have the 21st pick which you could potentially package and move up or otherwise deploy. Hauser is a useful player but easily replaced. Scheierman may be able to replace him.
It's a great thought. If you combine it with the use of our TPE, the end of the trade could be:
We lose Hauser
A third team gets Hauser and trades us a 1st
We trade two 1sts to a team like the Rockets for Smith Jr. or the Bucks for Turner.
Trading Hauser and one of 1sts for a stretch 5 difference-maker would be a roster upgrade.