This is why I think the devourer golem and, to a lesser extent, the Dyson Sphere are strategically interesting minor factions while many of the others are not. The Devourer Golem passing through an enemy system could very well bring forward your plans to take that system since it will soften it up for you, while a stream of friendly dyson gatlings (assuming that they're now as scary as they were back in the 3.x days) may similarly make you decide to send less or no ships to defend that planet (if the planet is yours).
In contrast, the friendly enclaves and resistance fighters are too weak / stupid to influence anything. Them attacking a planet is not going to bring forward or delay my plans for taking that planet. They just add a bit of flavour to the game, making it feel a bit more like a real world with several little powerless factions, but they're not strategically interesting.
In a similar vein, many of the hostile minor factions are also strategically uninteresting. Hostile enclaves, resistance fighters/marauders, wardens etc are just pests that annoy you and need to be slapped down. There's little or nothing the player can do to prevent them from coming (at least with astro trains you can kill train stations), and when they do come the player is obliged to send a little force to deal with it, but the threat is rarely at a level where the player risks loss if they're not dealt with. Personally I play all CPA waves, so the existing turret defences on all bordering planets are usually enough to blast through any attacks from these factions without me lifting a finger. They're like mosquitos in real life: annoying, can't really be prevented and don't add much of value to the game.
In conclusion, it'd be nice if a bit more was added to these fairly generic factions to make them more strategically interesting. Things like adding ways to prevent them from coming/bribing them off/killing their bases/etc (when they're hostile) or miniquests/sending them aid/gifting them a planet/etc to make them stronger (when they're friendly), making them a bigger threat in general (so that the players actually are scared of them, like mining golems and devourer golems), or make them raise/lower ai progress if they're not dealt with properly or if you do deal with them properly.
