Howdy Kevin,
1. Yes, keyboard shortcuts would definitely be nice... and easy to implement.
2. Yes, we have this one on the books, as well as the ability to set a default specification for NULL support so you don't have to manually change each field separately.
3. Not sure, maybe I'm not thinking on the same lines as you, but you can create custom fields outside of the .designer.* file that are unbound. There's really no reason for us to do this in the BOMapper since you can easily do it in the main code file. We have a help topic on adding custom, bindable fields to a business object, and I believe there's another topic in the VB tutorial that goes over adding custom fields as well.
3a. Now, changing the names on fields is a completely different story, and is already on the list of enhancement requests (i.e.: you have a "Count" field in the database, and when the BOMapper creates the designer file, that Count field conflicts with the Count field already on the object).
4. This one would be slightly more difficult, and might not be worth the effort, since the required fields are managed through the Visual Studio code serialization mechanism rather than by us generating the code manually, but thanks for bringing it to our attention