I love the gallery data connection feature - we're going through some big systems architecture changes, resulting in new locations for many datasets. Having a single place in the Gallery Admin area to update connection information works beautifully.
We're running into issues with the gallery-hosted data connections when trying to run some apps on our private gallery though. The trouble comes up when the gallery-hosted data connection appears inside a macro that's part of an app. We get an "Unable to translate alias" error when trying to run these types of apps.
If we have an app using gallery-hosted data connections that are outside of a macro, the gallery is able to resolve the connection alias fine and work properly. The issue only appears when the gallery data connection is part of a macro used inside an app.
We use macros a lot in our app development because it allows us to use standard methods for accomplishing common tasks. Using macros also enables us to set up automated testing workflows to make sure our processes produce expected results. As it is, we're unable to take full advantage of the gallery-hosted data connections because they don't work within macros, and instead have to continue using hardcoded connection strings. These are a bigger maintenance burden as our underlying systems evolve and are updated.