With the newly added maps, there's indeed that feeling of "emptyness", don't worry, that will be fixed adding npc and stuff here and there...
For now, the places to find monsters more easily would be cities, such as Hydlaa, with the Arena building, for instance.
Mind you, NPC fighting is bugged right now, so it won't really make much of a difference that you find, or not, a monster to kill.
Take this chance, to think about how your char should be, in terms of roleplay, a better business for the long term, than killing monsters.
