Are you planning it for after your ceremony or at the end of the night?
I like the ribbon wand idea for a day-time exit, or colourful confetti.
I think sparklers have become so popular because a lot of people are doing their grad exits as they leave the reception so it really lights the way out. But glow sticks could be cool, or even get guests to use their cellphone cameras and have the photographer use a more shallow depth of field so you get that nice diffused look from the lights (we did this on a music video shoot I worked on one time and it looked super cool)
bubbles, glow sticks (could see if you could get all the same colour so it looks less rave-y, lol), dried flowers/petals, biodegradable confetti (or seed paper cut outs of shapes like hearts), ribbon wands (attached picture, wands with ribbons and sometimes bells for people to wave, they look really cute)
Hi there! My fiancé and I might do bubbles for our guests. We have “herd” of nephews and nieces so we wanted something that would be fun for them too. I am looking at the 100 pack on Amazon. It’s not too expensive. Another thought is having a eco-friendly grand exit such as using herbs or dried flowers as something to toss.