I could write pages however (given I have two young kids to put to bed) I’ll keep my response brief. I would definitely look at extending the options exercise period mainly if you are a private company.
Considering your staff, shares are not liquid (for private companies) so, as an employee, you are forced to exercise when leaving and it can be financially difficult (you will pay the exercise price and receives shares that cannot be sold). By allowing a longer exercise period you provide more flexibility for employees who wish to be alumni investing for the longer term.
From the companies point of view alumni can still be very valuable even when they leave. They will talk with future employees and customers and give a view of your business. If they are holding options they will generally talk a lot more positively.
So all in all I’d say extending makes a lot of sense. Good luck!!