My go-to tactic as a Romulan is pretty much basic cloaking procedure.
Defense:
Vs. seeking weapons, keep outside range 5-7, and ensure you're going slow enough to decelerate rapidly. If you're charging weapons, most likely you are. When your opponent fires seekers at you, IMMEDIATELY nail the e-brake and cloak simultaneously. This causes all seeking weapons to gradually lose their lock. If performed outside range 10, nothing tan touch you. Closer is risky, and should never be attempted inside range 5 without a weasel.
Offense:
Basically, stay cloaked while you charge, decloak once to draw seekers, immediately cloak again, then decloak once everything has dissappeared. Fire, rinse, and repeat. It is often necessary to adjust your phaser slider to 1/3 to match the charge rate of your plasma since you're cloaked and can't fire faster anyway.