How many track days/miles have you had on the links before they are breaking? We have not had that issue in here ..... after some 70 track events, I now have Comptech's pro suspension, Dali's track bar front at stiffest and rear at middle, Type R braces, and run on Toyo RA1 and don't seem to have oversteer issue. If anything, I have a bit of understeer tracking out and by softening the front dampener setting two clicks compared to the rear may have solved that problem; if I need more, I will loosen the rear suspension one hole - at the edge, fine tuning is track specific and where the real big boys play the game.
But looking at your first video, I suspect your suspension setup is off. Too much steering input which tells me you don't have enough front grip. I too agree that 33/40 cold is WAY too much on street tires. Having no rear sway bar is a totally different ball game and has to match your overall suspension. YMMV.
