This is actually an option if you level treasure cartography. I really miss the different colors if I'm playing an alt that doesn't have them unlocked yet.
I kind of like it that leveling skills gives you more map options, but I wish the starter map making options were less limited. When I started playing, I diligently marked every location of interest on the newbie island and promptly ran out of map pins.
I think I'd like it if everyone started out having 2-3 colors available and more map pins than right now, and then leveling foraging or treasure cartography could give you super special stuff like the layers Shieldbreaker suggested (I like that), or maybe just silly frills like pins that look like a flag or something.