I don't have any kids, but I guess this is what it feels like to choose a favorite.
Of course BSG, Star Trek and The Expanse are among my favorites. The Expanse novels are also highly recommended.
But a few other shows come to mind:
Almost Human (2013)
Ran for only one season, but really enjoyed it. Featuring Karl Urban and Michael Ealy.
Stargate Universe (2009-2011)
I really really liked this one. It was a bit slow at times, but man, the discovery of "a structure behind creation, a structure visible in the background radiation" (if I remember correctly) really got me. A really cool hard scifi concept. I almost cried when it was cancelled. Also, I totally didn't watch it for Julia Benson's boobies. Was she in it? Really? I did not know that. I had no idea...
Space: Above and Beyond (1995-1996)
Marines in space. Always cool. Probably isn't as cool a show when I watch it today, but I remember it as really cool. Please don't rob me of my cool memories.
Sliders (1995-2000)
This should be remade. I mean, who wouldn't wanna run away from this world right now, right?
Colony (2016-2018)
Felt a bit like the "V" (1984) of our generation. Fine, fine... your generation (God, I feel old).
Rick & Morty
This can be classified as scifi right? Probably the best show in the multiverse.