At 1000bb from the small blind, restraint is the whole strategy: a tight net of hands that can win a mountain.
3-betting is nearly reserved for the top of the deck. Position and nut potential dictate everything else; offsuit broadways are mostly gone.
Small blind against a cutoff steal: mostly 3-bet or fold. Flatting builds multiway pots you play blind-first for the rest of the hand.
Assumes a ~4bb open; 3-bet to ~3x the open in position, ~4x from the blinds — larger as stacks deepen.