When we started developing the world the game is set in we already had ideas about our art style. Rather than try to emulate classic CRPGs directly we wanted something bolder. We didn't have the people or budget to produce exceptionally detailed art in the quantity we would need and the usual art style of RPGs under such constraints is typically rather muddled and we don't find very engaging. We wanted to make something distinctive. For ideas we looked at the art that inspired the earliest CRPG developers from the 70s and early 80s. Perhaps the art they would've picked if they'd had no technical limitations. Much of this art wouldn't lend itself to a distinctive 3D art style, but we were very charmed by certain album covers, pulp novel covers, and European comics.
This art had strong bright colors but often a smaller palette.
They freely mixed fantasy and sci-fi
The worlds and characters they showed felt immediately interesting to explore
This art style could certainly be applied to a very traditional vaguely medieval world that encompasses most RPGs, but our art inspirations were rarely so straight forward. In the 70s the 'fantasy' and 'sci-fi' genres had not become so clearly defined and much of the art freely mixed wizards and space ships. Jack Vance, where D&D gets its magic system, rarely had straight forward fantasy without weird sci-fi elements lurking at the margins. The earliest CRPGs also tended to be this way where you encounter sci-fi elements in Ultima, Might and Magic, and Wizardry. We started to call this 'cosmic fantasy' or perhaps more simply what a stoner metal head D&D player in the 80s would've liked.