Rangers are essentially unpromoted Gunners until about lv25+. The godly speed and power boost to revolvers aren't noticable until the later levels. Until then, revolvers still suck and you're still left with bowguns/autoguns for comboing >_>
With that said, Rangers are actually the most technical in PvP. Their skills can't be spammed as easily as the other subclasses'. Where mechanics can use their bots to annoy and chip away at the opponent's health, spitfires can buff their bullet damage and rely on AoEs like their grenades and shotgun, and launchers have damaging, super long-ranged weapons, rangers have to chain their skills with regular attacking to deal any significant damage. Rangers also have to get the closest to their enemy, so they run the risk of getting super-armor raped by other classes.