Another possible problem: unintuitive gameplay.
When you play a regular fighter or Smash Bros, you want to inflict as much damage as possible while taking as little as possible. Hence, you have a balance of offense and defense. In PSASBR, there's relatively little reason to defend, especially since a Kill counts for more than a Death. Honestly, being hit only matters when somebody is using a Super Move, and other than the Level 3's those can be tricky for noobs to land.
Love and tolerate.