He's only got his optic blasts. Everyone else either has omega level power output, a, a second mutation or in Logan( Howlett) and Creed's chase a genetically divergent mutant strain.
Why Scott don't have anything else? And no understanding trigonometry well doesn't count.
Cyclops is the perfect example of an Alpha-level mutant. To be honest, most of the known X-Men aren't omega-level.
His power is devastating and destructive but definitely not on a global scale. You could even argue he was Beta-level but graduated to an Alpha-level threat after training.
I'd argue Cyclops, Nightcrawler, Colossus, Banshee, Beast, Archangel, Bishop, Rogue, Gambit (after his brain surgery from Mr. Sinister) and even arguably Wolverine are all Alpha level.
Storm, Jean, Xavier, Magneto, and Scarlet Witch are able to cause catastrophes on a global scale, so that's why they're omega-level.