Hey Jaswitha12 I'm sorry if you never received a response on this. I actually don't come to the forums that often. You probably already answered this question for yourself. 
My two cents is that Sins, Stellaris and Endless Space 2 (ESP2) play very differently. I always approach these games the same way I read a novel: a heavy dose of suspended disbelief.
I hang my reality hat at the door and become something that lives in that universe. It frees you up to enjoy the good with the bad. It's also cheaper than therapy.
ESP2 is a pretty game. It's very relaxing. You can play it when you're half asleep. I fire it up to listen to the music sometimes but I don't play it anymore.
Stellaris has evolved into a behemoth. It has more DLC than One Piece has episodes. Watch some videos on which DLC to buy and why so that you can spend as little cash as possible but still experience all that Stellaris offers. Also I believe that as long as the host has a certain DLC you can access it's features. Paradox did the community a favor there. I play this maybe once a year now. Just to keep my toes in. If Stellaris has a flaw in it's design, this is my opinion, is that it doesn't let you control individual units, but of course if it did then it wouldn't be Stellaris anymore. Stellaris is viewed from 40,000 feet. You are a monarch or a muse that influences events on a grand scale.
Sins is the only game that scratches "that itch" for me. We all know what it is but it's so hard to put into words. To feel the dirt under our fingernails. To be bloody when we walk off the field together. Losing sleep over stupid decisions two days later. And because we are spoiled by the Sins modding community I get to be Riker from the alternate reality where the Borg have won.
Ultimately any game that doesn't give me what Sins and it's modding community lavish upon me will seldom be more than background music as I go about my daily tasks.
