Seems like the only PWT problems are the combination of high PS, Boost action, 360 firing, 60 minute rounds, and MOV.
High PS + Boost allows you to arc dodge, the 360 firing allows you to arc dodge without severe shooting repercussions, 60 minute rounds means large numbers of ships + less actual turns than needed to effectively block a large base ship AND kill it, and MOV means that high defense, high points ships win more games.
Its a far more complicated issue than simply "PWTs are too good" because there is a perfect storm of conditions that favor fat ships in general.