I don't think the Dimensional Gap contains parallel worlds? Like, each parallel world should have its own Dimensional Gap.
Naw, I'm pretty sure you need a CRT for something as major as that. Dimensional Gap stuff could affect the LN characters (God Tiers) because Great Red and Ophis maintain/stabilize it and keep the worlds balanced with each other. It's basically a linchpin scenario, similar to Bleach's cosmology.
So you're gonna need to define what exactly the Dimensional Gap is and maybe also the size of the worlds maintained (Earth, Underworld, Heaven, etc.
@MasqueTLDF
I've got no solid opinion on the sizes and all, so you won't see me in the CRT but I'd say it's definitely needed to clear things up and get other opinions before making something massive like that.