Your biggest foe with turn 5 will be keeping 8 people interested in wiping over and over for 1-2 weeks every night... Why you see so many companies stuck on turn 5 is they lack the dedication to willingly put forth the effort, so they happily farm 1-4. Turn 5 is unforgiving, and does not care how much you like your friend that simply cannot handle learning the fight, so if someone has no chance of doing it, start looking for someone that can.