Thanks for all the comments on this, both here and by email.
Overall the feedback has been positive, though with some understandable caution. Change is never easy, and for long term users the edit interface used here has been the same since PhpGedView was created in about 2002.
I have therefore decided to progress this and have included it in the developing code for the next release. That will now be 3.2.0, as this is a significant change.