Indeed there is a lot of exciting stuff missing from B4A which makes it hard to create professional grade apps.
For me, a professional-grade code is stable, thoroughly tested with a great number of devices in many different situations, and mostly bug-free. That excludes unfortunately 90% of the new views growing like mushrooms on Github and most libraries published in the B4A forum (my own libs included). They are made by people who don't have (or take) the time to test them carefully or enough devices to ensure that the lib works fine on most of them. Some of these Java libs, that you can try with apps like "Libraries for developpers", are so unstable or so badly written that I couldn't imagine using them without rewriting them. So, for me, "professional" is not the word that I would use to describe all this "exciting stuff" of the Java world, and wrapping it does not imply that you'll get quality components. Moreover Google changes the rules regularly so you can never be sure that this code will work fine with any new Android version.
I don't know exactly why the views of B4A are minimalist compared to what the Java world can offer but I can understand such a choice. B4A provides a set of views that should work on all devices, in all situations. It's not impressive, not fancy, but it's built on a basis that Google should not change in the future. It is a really professional approach. But, on the other hand, it's also a big problem as the libraries that all modern developpers want in their app are created by users, and these users do not share their source code. So you have no guarantee that the developper (including me) will still be there in a few months to fix a bug ruining your app, and you cannot fix it yourself. You face a dilemna that does not really exists for Java developpers (a library for them is usually a source code, not a compiled jar, and they have a direct access to the Android API): using a library to get improved or new views and taking the risk that it does not work as expected sooner or later, or using only the basic views of B4A and having to write a lot of code to replicate some Java views (if possible). So, for me, B4A cannot be used professionally without writing your own code. You cannot rely mostly on the work done by other users, but it's only my opinion of course.
And if you want to replicate the look & feel of some apps, note that many of them use private code, Google included (for example, Google did not release all views used in Google Now and Google Plus).
