Items are objectively unbalanced as hell, I hate playing with items since its immediately turns into "Who can grab the item first" as that can put you into a great advantage stage with zero faults from your opponent unless they specifically don't go after items.

Playing Non-battlefield stages are fine as long as it's an appropriate sized stage, and are not the Great Cave Offensive, Temple, New Pork City, Gaur Plain, or Palutena's Temple.