In my opinion, the theme is definitely interesting, but the map doesn't really look that good and all. The main PvP space is interrupted by those structures which makes it look cramped and small. I'm not sure wether a Duels map should have lava and fire in it, there was a map that used to have a lava lake and it got covered with glass because it was just too annoying, so I don't think that's a good idea. Sandstone walls are 1.14+ by the way, and CubeCraft's Duels runs on 1.9 so those would have to be removed. And even if they could stay, they don't look good and seem as if it'll only make the map take longer to load.
Perhaps this map would be a good addition to CubeCraft if it had more detail in it, and if the PvP space was bigger and didn't have so many obstacles around it. In my most sincere opinion, even if the map doesn't look necessarily bad, the quality of the build just isn't the best and definitely not fitting for a server like CubeCraft.