What spoiler & camber correctors do you have?
Talking about the high speed handling, my V6 is lowered on eibach springs and bilstein dampers, poly-bushed, eibach camber correctors and cup spoiler. I was driving on the autobahn just outside of Frankfurt and gave her a good run, an indicated 148mph on the speedo before I had to back off and it was a bit light and twitchy at that speed!
Not too sure about a standard GTV but I can tell you the big BMW's and Audi's just seemed to be planted rock solid at the same speed.
I would imagine you must have come across most of the different setup's that have been offered for the GTV in regard to the suspension, which combo have you found to be the best all round? I use mine for a mix of normal driving, long distance trips and the occasional track stint, and have found the current setup to be ok, just think that the ability to adjust the dampers and ride height may be useful from time to time.
To be honest as I don't do a lot of miles in any of the cars it's diffficult to say but....a really good std set up is still hard to beat, IMO. Poly bushes, Konis etc will always feel better than what you've changed them for....normally knackered units.
I do like the lowered look & feel either with std shocks, or adj Konis, especially at speed....but at low speed a bit harsh/bouncy. Konis & Eibachs, set on the softest setting, is probably my favourite modified for everyday driving. Too many variables, & personal preferences, to advise an ulimate set up.
My daily winter drive is an Isuzu Vehicross which has probably the hardest std suspension of any production vehicle...but I love it
If I wanted a smooth comfy ride I'd keep a Jag/BMW/Merc/Lexus etc.....but I only do short blasts so a GTV on whatever is a good choice.