I think it all depends on the game and situation.
For drive-bys and hitting multiple and/or moving targets, ROF is more useful.
If enemies are stunned when they are hit and this prevents them from moving or returning fire, then ROF is more useful as it suppresses the enemy as well as damaging them.
For large, distant and unsuppressable targets, then damage is more important, especially as damage usually also means range, which allows you to keep your distance and take down the target.
Also, if the targets have a damage threshold or modular weapons that can be disabled, then damage is more useful as each shot can have a large effect.