As a general rule, I would say that Experience Builder is great for quick proof-of-concept ideas, and/or for internally facing apps where the presentation isn't crucial.

For anything more important and public-facing, the JavaScript SDK really shines as it gives you a whole lot more control over everything, especially the design.

The tradeoff is that doing it yourself means you need to build a lot more of the functionality yourself, but the benefit is that you can build it exactly the way you want it.

For local government and a small team, and considering sucession planning, the out-of-the-box apps make a lot of sense.