Starlife,
I think I proposed a MoM NES once at some point.
MoM included the twin worlds (Arcanus/Myrror), which your setting doesn't have.
I think half-orc and half-elf cultures don't make any sense. They would be different races, and I'd rather see all MoM races (klackons, lizardmen, trolls, draconians, beastmen, even gnolls) than these useless hybrids.
The big points in MoM were to build up some cities, and build extra strong units there (be they slingers, hammerhands or paladins). In particular, what was really fun was the ability to mix races. Conquering a dwarven city on Myrror ment being able, after a while, to field dwarven units. Of course, some races were better at maintaining order with other races, but your proposed ruleset makes that impossible. MoM wasn't a race conquering the world, but a wizard uniting different races under his rule (of course, you could raze every klackon city you met, but still, razing a trollish, halfling or dwarven city sounds very stupid)
The ruleset not only doesn't allow taking over other races, but it also doesn't describe the variety of units. It doesn't have to be precise. Most units are similar anyway, but each race had a few special units that made for different strategies: Griffons, paladins, slingers, warlocks, all played differently, and a MoM NES would have to allow these unique units into account somehow.
The other strong point of MoM, apart from the magic variety, was the heroes and the awesome forging system. Heroes would eventually make up stacks of doom, with a few flying invisible champions impervious to most attacks thanks to enchantment and custom über-equipment. These are much more tricky to handle in a NES, as they should be limited in numbers (in particular magic items), and power to some extent (a guy single-handedly beating an army of spearmen by flying over them and shooting arrows is a bit hard to believe).
Regarding hexes, they are ok with me. They make the NES a boardgame, but with simple movement rules they can be neat.