I'm just gonna shoot these 2 ideas into the dark, because I think it would make the competitive multiplayer scene more fun

There was a custom map for starcraft 2 called desert strike, which involved building structures which would periodically spawn troops (in the formation you set up your buildings, or a default arrangement).

It was a simple "RTS-lite" sort of gameplay, greatly simplifying eco options and removing micro control entirely. Eventually you'd kind of "cap out" what is possible pretty fast, but this is the basis of my suggestion.

Maybe introduce something like a single controllable and customizable "hero unit" to add a layer of complexity?

I guess for Sins it would translate to a system formation like this;

Player 1 Planet - Player 2 Planet - Player 3 Planet

Team 1 Spawn and base Planet (With Defenses)

Team 1 "Bunker" Planet (Bonus for first team that kills other teams bunker)

Central Planet for combat

Team 2 "Bunker" Planet

Team 2 Base Planet

Player 4 Planet - Player 5 Planet - Player 6 Planet

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Another Idea would be something more focused on a customizable capital ship system, pitting you and friends against waves of enemies maybe?

So I'd have to balance across actual skills, speed, durability, shields, shield burst, armor, armor defense, armor regen, hull, hull regen, maybe even turret placements... or maybe something modular like armored core 6.

Could be two capital ships if one is too limited in complexity and fun.

Or to make it pvp, a dota concept.

Or something persistent where you could save and continue your "hero" cap across some multiplayer scenario map.

Bye ideas, off you go into the void of the internet.