ocean bough
I recommend adding more fights where we can ask other to come and help us same as outland rift fights. such collaboration is fun and can help people to progress as a team.
maybe make some new currency or tickets that we collect from weekly or daily events such as goblin or domains...etc and these tickets allows us to request for help in any fight such as vortex, weekly bosses, fey, pillar, where it allows the ally to put 2 heroes and the person who requested the help to put 3 same as rift. this will help free to play players and it is a great teamwork.