Hey-a !!!
I LOVE comedy and actually for my captains speech in year 11 (I didn't get the position tho

) i made the whole thing a bit and didn't ACTUALLY talk about why i should be captain and people still talk to me about it more than a year later. It was a really memorable moment for me.
Comedy a great way to both bring heart to a speech and make sure it doesn't get too soppy!!! So these are a few suggestions I have for comedy since heart isn't really my forte with my own being a icy void.
I think a great way to be remembered is to incorporate some kind of physical comedy/props in and have a repeating joke. For example have 2 copies of your speech, one in your pocket and one to read off from. At some point in the speech have some kind of joke that result in you tearing the sheet in half. And then getting the other copy out of your pocket.
-Talk about dead memes.
-Say some speech.
-Mention dead memes again.
-Pull out the 2 fidget spinners in your pockets and spin one in each hand as you dab.
If you can, it would be cool if you could get one of your friends on board and ask some kind of question that they can come on and answer. Points if they are dressed up.
Try to open your speech with some kind of one-liner. Points if it's unexpected or slightly offensive. I.e. "I had a terrible school experience. I went to {insert your school's name}" Of course immediately turn around and and point out that its a joke and you can use it s an opportunity to talk about your experience or recount a story. It'll catch the audience by surprise and ensure they'll want to pay attention to you as you are going to entertain them.
This suggestions on the dumber side but rference something in popular media that you know the younger people in the audience will understand and can laugh at i.e. Jake Paul. Then remark on the fact that adults who didn't get it still laughed at it. I.e. "Why are you laughing, you don't even who/what I'm talking about."
You don't have to use my suggestions but i have a few more if you are interested.
Any way, good luck. Go get 'em and make 'm weep & laugh simultaneously.