Your list looks quality indeed. Assuming that you witnessed Baresi's and Maradona's era, if you don't mind me asking, I'd like to hear from you about the likes of Sammer, Kohler or Bergomi and Desailly in their heydays and how you would find them in a comparison with let's say, Nesta as you prefer him to those players. Cause as I heard from one of my elder cousins, Sammer and Kohler are said to have been truly magnificent in every aspect of defence and a lot more complete, comparing 00's defender such as Nesta and Cannavaro. Not that I take it as an unquestionable fact but maybe given yours and others opinions on this subject, I'd make my personal opinion clear and accurate as much as possible.
mmmh, i wouldn't agree with your cousins honestly. sammer and kohler were indeed absolutely amazing, but i wouldn't say they were more complete than nesta and cannavaro. they were just completely different defenders, who played in a period when football was much different than today.
kohler was a world class stopper (to make it simple, a "stopper" is a cb a la vidic). he was truly magnificent in his prime. his heading skills were absolutely ridiculous. his anticipation was almost cannavaro-esque (wich is as close as u'll get to perfection, when it comes to anticipation)... positioning-wise on par with fabio. i believe the only difference between cannavaro's anticipating diagonals and jurgen's were due to timing: cannavaro's timing was freaking insane, kohler's timing was just not that perfect...... still, it's like looking for a pimple on botticelli's venus, as we're talking about a proper world class player. however he was not really what u would define a complete cb. the stopper position is quite a narrow, limited role, and jurgen was never more than a world class stopper.
moreover i wouldn't mention him alongside the absolute legends. in my
personal opinion, to be worthy of the legend status, u gotta be absolutely unique. there was only 1 beckembauer in football history, only 1 baresi, only 1 nesta, 1 scirea. legends are uncomparable, not even to each others. no one is ever gonna be labeled "the new baresi", because if we'll ever get to see a cb as gifted as he was, then comparing this new awesome player to any other player (even a legend like baresi) would be unappropriate, reductive and degrading for both baresi and this new "legend in the making".
think of messi, no reasonable man would define messi as "the new maradona".... messi is just too good to be compared to anyone.... and so was maradona. that's why we use the label "legends" afterall: so we can remark their hall of fame status, without having to compare them to each others or rank them (wich would be impossible).
desailly, kohler, bergomi and sammer were amazing world class players, but they were not unique and uncomparable to any other cb in history, so i wouldn't call them legends.
sammer imo had a great luck, because he was a libero in a time when liberos were becoming an endangered species. the 90s were a decade full of changes. sacchi's revolution (1988-1990) had changed the very concept of defending for ever and that, combined with the growing importance of the offside trap in coaches' gameplans, meant that there was no place anymore for a libero on a football pitch.
the thing is, matthias was actually so fucking good at his job that, even though from a tactical point of view his very presence on the pitch was a liability, it was just impossible not to line him up anyway.
so credit to sammer for being able to emerge and separate himself in a time were liberos were just disappeared from the scene.... but that was also quite a lucky coincidence for him. because, since he was basically the only great libero in the world, he got huge praises and accolades. much more than he actually deserved. if only he had been born 10 years before (when the libero was the cornerstone of basically every defensive line and there were dozens of great liberos all over europe), his history and his reputation would have been very different.
mind u, i'm not saying sammer wasn't a great player. he was a world class player.... and would have deserved the "world class" label also if he had played during the libero's golden era.
but a legend? no. there already are 3 legendary liberos in football history (beckembauer, baresi and scirea) and, as good as sammer was, he was just nowhere near as good as them. not even close. and i have watched plenty of baresi, scirea and beckembauer (even though i was born only in 1980), so i know what i'm talking about (like u, i also find it unappropriate to judge players u haven't seen enough).
anyway, like many already stated, this is no scientific matter and there are no undebeatable certainties, so my opinion is just as valuable as anyone else's (including your cousins').
Chicks are all around, though. 
