This I like quite a bit. It honors the principle that it is usually pleasing to have the primary color of the tie echo a secondary color in the shirt, and the principle that it is usually pleasing to have the tie primary be a complementary contrast with the ground and secondary in the coat.
The solid tie on a tattersall with a glen plaid coat avoids one small problem with @zr3rs's combination: the neats on the tie are very similar in scale to the check in his tattersall. That's what makes the ensemble pretty busy, as he put it. If the tie had considerably bigger medallions, like in some of Urban Compostition's recent postings, the busy-ness would be reduced.
I think I should ask you to do a few posts. Articulating principles is a useful exercise, and that was part of the point of the Lounge.
We can all agree that fundamentally, dressing well is a practical/perceptual skill but that articulating those principles we implicitly rely on is useful and a good way to teach others.
So, want to run through a few of your principles, with pics and illustrations of what works and what doesn't? You've done a bit above.
I agree with @greger that the Pitti pic runs afoul of the simple matchy-matchy PS/tie rule (i.e. don't do it). I suppose that there's a thread to pic apart decent Pitti fits, but maybe next Pitti.