Over the last 2 weeks I have been working on Weld's boot performance, and have managed to reduce it considerably (see here for full details).
At the moment the biggest bottleneck is classloading, which consumes about 50% of the startup time. I think a possible solution to this in as7 would be to begin loading the classes eagerly and asynchronously, as soon as a module with a beans.xml is discovered, so that by the time weld starts to boot the majority of the classloading has already been completed.
Does this sound like a workable approach?