We need a social aspect to the game, if Horde mode was to be a community effort against zenos it would break the game open. If we had hub where we could customize, purchase, unlock cosmetics for our preferred chapter, then returned to horde mode in an effort to combat zenos across multiple planets depending on the on going event at the time, the game would be unstoppable and have unlimited replay-ability with how incredible the gameplay loop is. Give us a communal purpose and open the game up with a squad base effort in community horde mode. 

Customization, currency, a shop, a friends list to meet other space marines you fight with, and continuous fight against the enemies of the imperium from event to event.

Please go ALL IN ON HORDE MODE

This would be great and i think it should be implemented in a helldivers 2 open maps fashion with more than 3 people squad . Modders have clearly shown that we can have way larger enemy waves and multiple allies at the same time without any performance issues , so it is perfectly doable. They should also implement firstborn 1st Company Veterans marines (with their dedicated weaponry and accurate loadouts) for that game mode (and Chaos marines aswell). In this way we would have a real 40k experience , providing big open battlefields and alot of variety in gameplay. Thats what horde mode should be imo 

I kinda have a bad feeling about Horde morde when the game functions like it does currently;

My prediction is endless Gunstrikes for 2 hours until the game crashes from too many Majoris spawns..

¯\_(ツ)_/¯

I am curious how they approach it though - Arena style, how are the enemies flooding in etc.