The only WB that might be OP right this moment is McMurrough, and its because of the Total Immunity. But thats also a skill JSA benefits from, because Karakuris are very powerful now, and they are Specialists. As for spamming cheap units, the cheap units used in many lists are not really for swarming, but rather cheerleading. Quality units and skillful decision making do matter more than just piling the board with cheap units. The cheap units I see are flash pulse bots and baggage bots. Sure, there are a few WB units, but most of the time they are irregular and there for don't contribute their order without a command token usage.