I think the issue is, everyone's playing the game for long enough that they don't stay at low level, and as such there's no low-level enemies for the early areas. So in a way, your gamedev skills have come back to bite you I suppose.
nah, i can see in the database there are plenty of accounts/teams spread over different levels/areas that have been there for a while now. people stop playing at different levels and their teams will stay in place.
if it would ever happen that there is no opponent available, the game matches you against an AI.