I've played a few of his designs, including the ones on better sites.
Aside from the aforementioned bunker style, what is interesting is that in many cases TWP/Thomson talk up the ground game, but then design a course almost entirely reliant upon an aerial game.
They are distinctly penal, especially the one I am most familiar with, but that penality is aimed at a very narrow range of players - mid single to mid teen handicappers. Anyone better is good enough to avoid the hazards, and anyone worse probably won't reach them anyway, since many hazards are designed to be at specific distances - unless there is water involved, which is far more in play for the average player than the good one.
What us clear is that they run out of inspiration very easily - there are usually one or two good holes that follow "normal" strategic principles, but then no more. You might also find one or two interesting greens, but then the others will be quite bland.
Moonah Links Open isn't actually that bad a routing - it is the bunker shape and placement, along with the greens design, that lets it down.