Perhaps a little radical, but, would it not just kind of be a similar structural height if you prune it where it's already branched? As opposed to bringing it down a bit further and letting it push branches from there? It's really up to you on how you want your plant to look.
Also, if you have had it in that pot for 4 years it's probably time to get a look at the roots. Adenium don't respect pots. They will break clay pots without prejudice. If your aiming for a unique look, you should raise the plant about 1-2" every time you repot to reveal the caudex.
Something like this
