I got a few small scratches/gouges on the reel hood on my rod. Any idea what I could use to fix it?

Black sharpie or nail polish.  That is an anodized coating on aluminum so you can’t truly fix it. 

Could try Birchwood aluminum black

Not much you can do to truly fix, besides a new locking nut, but that's too much for something you can notice without a magnifying glass.

Black Sharpie. Aka "anodizing on a stick"

Those are character age marks. Leave them as is.  Wanna compare scars?

It’s just going to keep happening, but I like keeping my stuff looking good. It just makes me feel better. I would go the nail polish route. You could even clear coat over it.

Yea you can try birchwood if it's black. It won't necessarily fix it but will darken it and that's about the best you can do i think. 

Birchwood Casey Aluminum Black isn't black, it's blue, to match gun blue.  

(too many people have tried it on antique lead-finished fly reels - didn't listen to me - and bemoaned the result)

JAX Aluminum Black available from jewelry suppliers is black.  

Both are sulfuric-acid bronzing the way they did it prewar (before anodize - final prewar coating was lampblack, with a sawdust dip before that)  

The bronzing result is more like a smut than a coating, but I've used JAX to cover scratches on antique fly reels.  Also to passivate newly tapped threads in castings.  

 

Here's the result using JAX where I cut a reel seat hood to let it open wide enough to fit a longer 72-mm reel foot on a surf reel

(this is before the JAX)

 

I vote with the Black Sharpie guys.  

Graphite paint is also worth a try.  

If I can make a suggestion. You might want to try a black paint pen or black nail polish. Though with the nail polish. You might get questions from your girl. Be prepared.