I like this idea, it is sort of like arena football.
It would be pretty entertaining to watch a 3v3 or 4v4 summer league. Could play 3x20min periods with no stoppages. Offside the defensive team would be given inside their blueline to take puck out. Penalties would have the player go to the box while play is still on etc etc. Only stoppages would be for goals when they would have a 30 second commercial break or something. Lots of young players would be happy to play in a league like this as it would be completely offensive minded.