Token Stamp
When I started using Roll20 I used the in-built tokens. They include hundreds for free, illustrations of heroes and monsters drawn as if from above. And they were fine and did the job. But then I started using circular tokens instead. If you buy an official D&D adventure through Roll20 it comes with all the tokens needed to play the module and they are circular tokens featuring artwork of the character or monster.
If you’re handy with Photoshop or similar you can make these yourself and import them to Roll20 - all you need to do is create a .png with a transparent background. But when a tool like Token Stamp exists you don’t need Photoshop at all. It even has a border preset that looks just like the official ones that D&D uses.
All you do is bring in a piece of artwork - this could be something you’ve drawn yourself or had commissioned, or an image you’ve found online - or nowadays one that has been created by AI! Choose your border type and then arrange the image inside the border (I like to keep quite close up on the face of the character as when you’re in Roll20 the tokens can be quite small) and then choose Download. You now have a token you can use within Roll20.