No one ever went to a movie and said "Well the acting was good, but the story was unbelievable."
Movies, like many creative efforts, start with the writing. You don't hire a bunch of actors and the say lets find a movie for you all. Movies start with a script.
Aside: Ads are currently running for MacGruber, Saturday night lives latest entry into the it worked as a sketch, so it must make a good film genre.
A script is a story. A story that moves us from one place to another - everything from to the Care Bears movie to Citizen Kane. *
MacGruber is a parody of the MacGyver. Each of the sketches is the same; MacGruber is faced with a bomb, which he fails to defuse. 45- 60 seconds each. That's it. That's the whole sketch.
For reference, a brief list of SNL movies that were complete cinematic stinkers:
A night at the Roxbury
Stuart saves his Family
Good SNL sketch based movies:
that's 3:1 against.
Without even seeing anything more than the trailers, here are the reasons it will be bad --
It will be like the sketch - one joke. Repeated.
It will not be like the sketch - it can't be. Every 1 min sketch ended with Mac Gruber being blown up.
Its an SNL based film (see above)
"Gag" based films (Blazing saddles, Airplane!, Hot shots, the various monty python's) are hard to write.
Based wholly on a tv show from the 80's.
BIG IDEA: Story matters. Writing matters. Get the basics of your project in place before you move forward.