Randolph West vouches for some Azure Data Studio extensions:
It’s worth mentioning that for the most part Azure Data Studio extensions are extremely lightweight, both in download size and memory usage. Installing this many on SQL Server Management Studio (SSMS) would slow it down dramatically.
Note: not all extensions can be installed from the Extensions pane. For many of them you must visit a website, download the VSIX file and install it manually using the File > Install Extension from VSIX Package menu option. In most cases you can trust extensions from reputable publishers, but always take care.
Randolph has quite a few more extensions than I do, but I can’t say any of those are a bad choice.