I think this is heavily an amph map.
Lava doesn't stop the jumpers from accessing the safe zone, and amph units are secretly all jumpers because Lobster exists. But generally i like the idea of a lava chasm island.
Technically, the lava will also require some shenanigans to get water and lava to coexist on the same map: typically, lava
is a type of damaging water, and Spring water is the plane {y=0}.
This map is narrow, and having three lengthwise domains makes it even more functionally narrow for factories that are locked to any of these domains, e.g. ships are locked to water, rovers are locked to not-water. This narrowness means low ability to maneuever in 1v1; in teamgames, this means that the game dissolves into a series of 1v1, one for each lane.
In both of these situations, porc-and-arty playstyle prevails; which means that factories with strong artillery will be favored (maybe alongside the safe-start air that is the only thing that retains ability to switch lanes at will, until Chainsaws and Artemis appear). This also gives a bonus to slow but powerful units; and this fits amphs very well.
Which, in this case, means ships will eventually dominate (or in 1v1, amph start into ships to capitalize on lane economy), as i expect Envoys and later Shoguns will be able to harass both south and north dry lanes with impunity.
The cliff in the middle will not be only accessible to amphs: it will be accessible to ship-plopping Recon commanders as well. Being a metal-heavy and very defensible thing, it will also intensify the slippery slope that's already inherent in narrow lane maps.
It would still be interesting to see someone try to implement it.