Choice 3: MOVE behind something. BONUS action hide. SHOOT with SA damage.Combat starts. Rogue is not hidden. Rogue wins initiative.
Choice 1: shoot an arrow, or run up and stab. No sneak attack.
Choice 2: “hold action until an enemy is next to an ally, then attack it” (note that this takes a bit more coordination if rogue is melee)
Edit: and even if you are hidden but out of range, waiting until an enemy is in range. And/or during combat, waiting for an enemy to poke their head out from behind cover.