Especially at Susuka, the lines are very important! Try to drift that ideal line. Not because you get the most points for it in Drfit Trails, but on this track the ideal line is pretty much the best drift line.
When you get that line nailed, go for a consistent amount of angle. This is achieved by not having to make very much corrections during the drift.
I've still not got this nailed, but practice makes perfect as you clearly know! Keep at it!