1/2A to B Rocket Gliders were added in a rules change proposal that passed in the most recent cycle. This becomes effective August 1st.
You can certainly put in a rules change proposal for DELD and/or DELA (see https://www.nar.org/contest-flying/rules-revision-process/ for how to do it). With over 7000 members in NAR and only a 122 even voting on rules changes this past cycle, you only have to convince a few it's a good idea.