In order to sign free agents like Hibbert or anyone else we need to renounce enough free agents to create the required cap space. Even if we renounce all our FAs we won't have enough cap space to sign KG, Hibbert and Bass. KG 10, Bass 5 and Hibbert at 15 puts us at around 60 Mil, and I think those are conservative estimates. What is the point of signing KG if we're going to have three rookies as part of the rotation? We can't even contend for a division title with that roster.
Also how do we get those players? Are you proposing we trade our 22nd pick for two of the Cavaliers early second rounders for example?
The difference between that roster and the one that took Miami to game 7 is the ADDITION of Lamb, White, Hibbert, Ezeli and the subptraction of Ray Allen. I would suggest that is a major upgrade.
From a salary perspective:
Pierce $16.8
Hibbert $12.0
Rondo $11.0
Garnett $8.0
Bass $4.0 (Cap Hold)
Pietrus Bi-annual Exception
Bradley $1.6
Stiemsma $1.0 (Cap hold)
Johnson $1.1 (Cap Hold
Dooling Vet Minimum
Moore $0.5
White $1.5
Ezeli $1.5
Lamb $1.0
Puts us at exactly $60 million in contracts and cap holds. I believe the cap should be almost exactly that amount. If it is lower, you can shave some off KG or Hibbert, or you could cut JJ Johnson. Alternatively, you could drop Bass and try to land a backup for around $2.5 per.
Finally, getting an extra late first or early second should not be to hard - maybe swap Jeff Green, or throw someone a future first, or a couple million dollars.