Honestly, the legacy maps that comes with Tableau are a little stale when it comes to design. There's nothing much you can change there. But, the good news is that you can add Mapbox maps in Tableau. But how to add Mapbox maps in Tableau? Simple, actually!
First, you need to create an account with Mapbox. It has a free account for upto 50,000 impressions per month. I would suggest you to create a free account initially (Don't worry if you see your account details as pay-as-you-go even after registering for a free account, it would still have the first 50,000 impressions free per month).
Once you have created the account, goto Mapbox Studio. Here you can create a Mabox map from scratch, or used a pre-defined style by clicking on New Style.
You can also click on Find inspiration in the style gallery on the left to go to their map gallery, you can recreate your own map by taking cues from the maps there, you can also add some of the map from the style gallery to your own style gallery and modify it. I have used the Le Shine map from the gallery to create this dashboard.
Once you have finished editing your map, click on the Share button on the top right, and the Share and develop box would popup.
In this popup box, under Developer resources, you will find an option which says Third party. Click on that, and then select Tableau from the dropdown below. Copy the URL by clicking on the clipboard button.
Once you have copied the Mapbox URL, close Mapbox and head over to Tableau. To integrate your map in Tableau, click Map > Background Maps > Map Services > Add > Mapbox Maps. Then paste in the share URL above. (This feature is available in Tableau 9.3 and above)
If you have followed the above steps correctly, you should be able to see the map in the worksheet background by now.
