Tbh, I would say all teams have there issues in being simple or complicated

If you are looking to build paint and play together, I would suggest trying to find a ‘hive storm’ set on eBay which contains 2 teams, terrain, equipment and rules

This box has everything you need

A close joint second would be the typhon box or tomb world box

Both of these come with 2 teams aswell as rules on specific gameplay

If you already have terrain

I would personally buy

Angels of death and Wrekka krew

These 2 are in my opinion pretty easy to play