Crying Suns - It has a similar fuel mechanic to FTL, which made me bounce off of it, but AFAIK it's a good game.
Star Traders: Frontiers - It's like a singleplayer MMO, if I had to sum it up short, and I'm sure someone on the internet would torch me for it. I burned out on it after a week or two, but it was an interesting concept.
Elite: Dangerous still exists as well.
Only medieval sim I know of is Kingdom Come: Deliverance.