But lets not debate this, it's very much so a pipe dream/crazy idea until Nintendo releases the game.
This game may have a Special Brawl mode that allows you to select multiple speeds; it's not that far-fetched.
Regardless, increasing the speed or allowing us to adjust it to our liking won't make the game much better. All indications are that ground speed is increased to be a little faster than Brawl, but things like aerial momentum preservation are still absent. Furthermore, many people have complained about there being too much lag.
People that aren't big on Melee or PM may think that those players just want a faster game. It is to my understanding, that the Melee/PM crowd want a more offensive-oriented game that gives you a great degree of control over your character's mobility and reactions; that entails far more than a simple speed change.
I haven't observed or read about any impressive combos being performed in the Smash demo, likely because the demo wasn't as combo friendly as the April Direct and character reveals displayed.
We don't know how old the demo was. Overall, it seems underwhelming to the greater competitive community. I don't blame them.
Casual fans and some players here have a different priority list when it comes to video games like Smash Bros.
I think my priority list is more in line with people that play games competitively.
On a scale of 1-5 with 1 being not at all important and 5 being very important, I'd make the following rankings.
Gameplay: 5
Balance: 4
Graphics: 3 or less
Music: 4
Story: 3 or less
Other Content: 3 or less
Fun is incredibly subjective, so I didn't include it in the rankings. Essentially, gameplay is the most important element to a game.
Casual fans and some other players tend to prioritize graphics and content over gameplay and things that add depth to the game.