Imo there is nothing dumber than building slow right now. If you can get Herro he's the perfect timeline fit. He's got 4 years left on his deal so you can help maximize the current win-ability of the team. After those 4 years you can transition the team to Keyonte if he's truly worthy and trade off Herro and get value out of him.I don't think trading for Herro if it is at a low price is crazy but I agree about wanting to build this slow or at least make sure that we are in a position to get our draft picks consistent minutes. As it stands right now we already have a serious minutes crunch and will have a very difficult time finding Hendricks and George consistent minutes.
Also if Hendricks is any good, the Jazz will have to decide between keeping him or Keyonte after those 4 years (and possibly add Sensabaugh to that). We will have too much money in Walker and Lauri to afford to max both those rookies.
Imo just get as many good players as possible. Getting these long term contracts that will be cheaper as time goes on gives you a lot of flexibility while winning now. There's no reason to not maximize winning now (within reason). We can't be bad enough to truly change the franchise future with a guaranteed star talent top pick.