I'd take peps treble team over the current one any day
Hypothetically, if you were able to play them against each other, without either them being able to know the other, I think the current one would win. What doomed the 2011 side was teams being able to figure out how to play against possession based teams. That side didn't have a plan B when someone would park the bus. This current team has the best of both worlds. If you compare possession numbers, they are almost the same as Pep's team yet they still have other tactical options.
The big difference is how the current team can also play on the counter. A midfield of Xavi/Iniesta/Busquets and Messi/Villa/Pedro weren't really accustomed and made to play on the break. The majority of the plays were slowly created through possession. That honestly didn't work when solid defensive teams understood how to play against them. The other big difference to Pep's team is the press. During the 2011 season, Pep made the team press when possession was lost, but it isn't as crazy as now. Rakitic, Suarez, and Neymar press like crazy for the entire duration of the game. Messi's defensive contribution is through the roof. Basically the entire midfield and forward line can press like never before.
You can look at this team as an evolution. When Pep's tiki taka was taking over Europe, no one really knew what to do about it and it steam rolled over the majority of teams. Then teams like counter attacking RM, defensive Chelsea, pressing A.Madrid, Bayern came and showed that you couldn't just keep possession and expect to win. This current side is an adaption of the old team. Even with the introduction of better players Neymar/Suarez trump Villa/Pedro, the change to the play-style had a lot bigger benefits. As far as I see, the current side doesn't really have any tactical weaknesses. They play well against the press, bus/defensive sides, possession teams, counter-attacking sides, etc. I still think the type of team that could beat team would likely have a stronger midfield but having bulls like Suarez and Rakitic running for 90 minutes helps prevent getting bullied off the field.
It will be interesting to see what will happen in the upcoming year. Dani Alves more or less left. During today's parade, he was crying and thanking the fans. In addition, Barca already bought Vidal, a rightback from Sevilla. Dream scenario would be for them to buy Verratti from PSG. At that point you would have a Verratti/Rakitic/Busquets midfield with 3 players who are unbelievable passers yet are all able to preform amazing defensive duties. Those three plus a Messi/Neymar/Suarez front is a team that likely can't be countered tactically. Hopefully the upcoming elections don't derail the team, because the only thing I see ruining it is the usual politics.