Good post this.[]
On my classic, I'm running Eagle F1's, standard springs and shocks, prodrive geometry and since the other week - whiteline front and rear anti roll bar links.
Cumulatively, all these mods have had an impact on the handling of the car, but the biggest change was brought about by the prodrive geometry set up as this pretty much eradicated the understeer I was experiencing - also as the geometry is not too agressive, it hasn't wrecked the tyres inner edges either.
As mentioned above, it's a balance and a compromise between track, road, comfort and ultimate handling ability. For me though - geometry might be the most boring mod, but it's definitely one of the most effective.