I actually remember the Marquez-Pique partnership very well...and long story short it paled in comparison to Pique and Puyol. We need a fighter, someone that reads the game well. Mascherano does this but his positional awareness is terrible...although it's not his fault since he shouldnt be a first choice CB in the first place.
Thiago Silva, Koscielny and Kompany...in that order is the type we need imo. Hummels is like 6'3-4 and is a MONSTER in the air- that is the only thing I'd be excited about with getting him.
Puyol is one of all time greatest defenders ,he is better than Pique or Marquez ever been and is even better the 3 you mentioned
so yes the Pique + Puyol was better than Marquez + Pique ,also Puyol + Marquez was better than Marquez + Pique
Now we are living in 2014 and we aren't getting Puyol again ,We aren't getting T.Silva or Kompany and there is very little chance we will get Koscielny
Our options are between Luiz/Hummels/Benatia/Mangala and the last one seems to be on his way to Man.City btw
Man.City/Manu/Barcelona and may be Chelsea,RM too are all going to try to find a new world class CB this season in addition to Barcelona .our options aren't too wide as ppl might think