MechaTarrasque
Hero
I think the problem is that there is an orc and a goblin entry in the MM, but not human and elf entries. The solution is simple: take out the orc/goblin/etc. humanoid entries from the MM, except for special cases like the Eye of Gruumsh, add some fluff for the NPC entries, like bandit, and make some new ones, like marauder (and make small and medium size versions of the NPC's). If marauders are always CE, then it doesn't really matter if they are human, orc, goblin, elf, dwarf, or whatnot.