this highly depends on how much time can you invest into this and how meticulous you want to be. Of the top of my head:
- The overall colour palette and texture of the map feels off. My first thought is something that resembles historical context like brown earthy shades or sepia instead of the green filling for the rectangle around the map. maybe even some form of roman mosaic pattern if it fits, no idea. Now, I know it might sound cringy, but if the background gives a classical vibe you can even incorporate things like roman ships between sea connections, similarly to biomes.
- Some of the borders between territories/bonuses look very fake. Looking at things like Mauretania +2 West Africa having territories separated by straight lines, and the Spanish +5 Islands being circles.
- Same topic, if it's possible to adjust the current borders to either geographical features or ancient roman province borders would be really cool, so it feels realistic. I can look into that and edit my post if there's ways to tackle that though my history knowledge is limited.
- the sea levels in the Mediterranean are way too wrong in the current map, + the quadrillion of missing islands in greece, malta, and west mediterranean, but also no realistic solution for these in my head.
The map also has some questionable terminology (not entirely sure, not an expert in ancient roman history). There's the trend of using provinces as bonuses and cities or areas as territories which makes sense overall. But it's weird to go for britain instead of britannia and egypt instead of aegyptus for example.
Also if it can be avoided using a city for the name of a whole territory it would feel more accurate in my head, but it's a whatever thing. For example, Italy didn't really have provinces till Augustus divided it and the city of Cannae would be Apulia and Terentum would be Calabria.
Also we have a bonus and a territory called Dacia.
And In Illyricum-Greece I'm crying cause the city of Athens is where the territory Achaia (not Achaea, i think) is, while the territory Athens is Thessaly or Thessalia in reality. Also if you google Illyricum you'll find really fast that Illyricum has absolutely nothing to do with that peninsula. Historically it would be more accurate to even call the bonus Achaia (which it kinda isn't since it's Achaia + Macedonia + Creta more or less) and change the territory Achaia to Corinth, that abides to the trend of using cities for territories and areas/provinces for bonuses.
Regardless, really appreciate the initiative, and feel free to send a message for any help and thank you for your work^^