I found a point of improvement when using Weld in an application using the new Java module system.
The core depends on the java.beans.Introspector.decaptalize() static method which is causing the dependency on whole java.desktop module (~12m of size) when loading a simple hello world application using Weld.
In order to fix that, a simple patch removing the dependency of that static method, either reimplementing it or using a third party library that contains the same feature.
I also noticed that Probe module depends on Bean Introspector, but it's non core (to be used by developers only). However, it can also be fixed using a lite Java Beans introspection library created to completely remove java.desktop dependency: https://github.com/panga/java-beans-lite