Don... don’t strighten em.

most scissors have a slight curve on them to ensure the two cutting edges meet.
Generally this is true.

Longer scissors have a two angle cutting angle 

Give me a call and take a look at Cowtown’s scissor collection. maybe even use
my scissor sharpening jig (liberated from a really old Manitoba fabric shop!

But do not straighten! you will regret it. They will not cut beyond the first
few inches if you do.

Regards Eric