I think we are all in agreement, putting the power down in the wet is not as simply as planting the right foot, moreover a featuring of the throttle and feed the power in slowly avoiding any power surges, especially as these are more aggressive on remapped turbo aspirated engines that tend to boost higher with more torque and prone to torque steer, even after all this your are still reliant on the road surface/temperature/tyres/PSI/tracking/weigh of the vehicle etc...
But i am still interested in improving this where ever possible, tyres are number 1 on list so its the, Flakin's, Vredestein Ultrac Sessanta or the Eagle F1 Asymmetric that i am gonna read up on and get a full set, i had the toyos Tr1 before and the eagle F1s GSD3's, not a bad tyre at all at all, but i always like to try something new, sometimes it pays off sometimes its doesn't(dunlop SP's for example)
In addition, there are a few posts about putting on a LSD differential and from the limited posts and web pages i have read, it is supposed to reduce torque steer(not nice in the wet, i know!) and wheel spin, so one of these maybe on the list also, only £585, but if helps i think over a few sets of tyres you may see some of your money back.
http://www.quaife.co.uk/Seat-Leon-Cupra-20V-Turbo-00-05MY-Quaife-ATB-Helical-LSD-differential
not sure if anyone would care to comment on there expierence of the Quaife LSD.