Designing Balanced 3-Bet Ranges: Value, Bluffs, and Playability

Short Answer
A balanced 3-bet range contains a clear value region, defensible bluff candidates, and a planned 4-bet response. Starting-hand strength alone is not enough.
Value Region
Value 3-bets need enough equity against the opener continuing range and enough playability when called. Later positions allow wider value; early positions require tighter value.
Bluff Region
Bluff 3-bets prefer blockers and postflop playability: selected suited aces, suited kings, and suited connectors. Hands with no blockers and poor playability should not be forced in for balance.
4-Bet Response
Know in advance which hands continue against 4-bets and which fold. A bluff range without folding discipline turns pressure into leakage.