My friend an I were talking a little while ago and he had a good question: What if the plane wasn't attacked by the Shi'Ar and the Summers lived as a regular family? What would happen once Scott and Alex developed their powers? Would Vulcan still end up crazy?  Would Chris Summers allow Professor X to take his kids in? Share your thoughts

@TheCrowbar: I don't know. Gabriel seemed cool in the flashbacks as Kid Vulcan but when he came back he went batsh*t... to be honest I'm surprised marvel hasn't played with this idea in a What If story before. Could've had Cable, X-Man or Rachel go back in time and to save their grandparents and uncle from their fates.

Scott would be able to control his powers and Alex would've been closer to him (already been said) 
 
I think he would still be an X-Man, but I don't think he'd be a member of the First Class (thus, not asked to be team leader by Prof. X). He wouldn't have the codename "Cyclops" and there's a chance he wouldn't have been as close as he was to Jean. Magneto, Storm, or Wolverine would probably be leading the team right now. Cable would probably have never been born. The Starjammers probably wouldn't exist. Emma would most likely be with someone else too.  
 
I would like to see what would happen to the whole mutant population without his leadership. Would it be better or worse?

I just realized....
 
Without the Starjammers who would've stopped D'ken from destroying the Universe?
 
So scratch my first answer:
 
We'd all be dead or a servant world to the Shi'ar throne.

Sounds like the good basis for a "what if" issue...  'The Brothers Summers'  
 
Vulcan would have turned out more normal and likely become a valued member of the X-Men...

What Crowbar said.

The summers family will be the most powerful family in earth.An actual family.