The Smash 4 tournament was a lot of fun to watch thats for sure. But a couple matches by the Bowser player Damien made me realize that Smash 4 may not be a very good competitive game because the defensive options are so incredibly strong. Shield dropping is the fastest its ever been and shield stun is the lowest we've ever seen in any Smash to date.
Even the commentators were shocked at how quick shield dropping is now . Again, Sakurai has made defensive play even stronger in this iteration of Smash which has been the trend in each Smash game.
In Smash 64, the shield was a horrible option. Shield stun was so long and shield dropping took so much time that by blocking attacks you were actually vulnerable to follow ups! Clearly this didn't make for a very good balance between offense and defense.
Melee's shield (the goldilocks of them all) was just slow enough that you had a few options of punishing out of shield but (with a few exceptions) those were mostly limited to punishing an attacker who poorly spaced their attacks on you. Shielding couldn't be punished and attacking a shield wasn't punishing unless you used the wrong attack/spacing. It was the best shield timing of all the Smash games because it made defense viable but not ideal. It forced players to get better and understand their characters better in order to not get punished on block.
Brawl's shield was so fast that many moves, even when spaced perfectly, were incredibly unsafe on block. Shield grabbing and dropping in Brawl was so strong that defensive play became ideal very early in the game's life. The scales of offense vs defense tipped severely into defense and the gameplay suffered greatly. In fact, over any other single change made from Melee to Brawl, the change of the shield timing had the most impact on making Brawl a defensive game. Why attack someone when they can shield it and punish you even if you space it right? The best characters in the game were able to beat this through various options like range, speed, a solid grab game or projectiles. It limited the viable cast from the huge roster we started with to a select few.
Now we come to Smash 4. This has the absolute fastest shield drop and lowest shield stun we have ever seen. Running up and shielding is extremely effective. A Bowser player completely shut down a Shiek and a Toon Link because nearly everything they did on his shield could be punished by dropping it and using one of his (compared to the rest of the cast) slow attacks. Bowser was punishing Shiek for too much lag. Let that sink in for a second. Now throw in increased landing lag on aerials... Okay, now add on spotdodging being even better and rolls being faster than ever.
Every single defensive tactic in Smash 4 has been buffed from Brawl. The scales of offense vs defense will very easily shift to defense unless characters have ways of beating shields. With shield breaking being slightly more viable (damaging shields seems easier now with certain attacks), that could add an additional way of dealing with shields. But if a character doesn't have range, a good grab game, speed, decent projectiles, or options of breaking the shield... then they may not be very viable. Even though I think he was a lot of fun when I played him, Villager is a good example of a character like that.
Unless Sakurai makes some changes (fingers are crossed here) from the E3 build that was being played at the San Diego Comic Con... then Smash 4 may end up being another title that the community forces to be competitive but won't actually be a very good game. No matter what happens, Smash 4 will have an even better run than Brawl did competitively. Lets just hope our concerns and constructive criticism are heard by the right people so this new game can become a worthy successor to the Smash title.
EDIT:
In response to many people saying "wait until release", I feel like I should put my answer on the first post to make it more visible