Need ideas to fill out forearm

I’ve hit a block with this tattoo (wife has a corresponding one of stars). I’m going to fill in the moon with a Palmetto blue color but would like to fill out the forearm. I was thinking of something from my Celtic or Nordic heritage. I’ve thought about making it my family’s tartan, kinda tattered.

I’m a history nerd so maybe something that represents South Carolina (home state). Possibly add something that has to do with hiking and the outdoors (I hike the AT a lot)

I don’t know…I’m stuck. My other forearm will have a series of roses and thistles intertwined and will be pretty beefy.