The main theme of my game is a 2010s zombie style game, kill zombies & players get tix, buy guns, more coming soon
What theme are you going for here… There’s a severe lack of detail in your post.
what @Polygonizised said, and also is it supposed to be green? Idk if its for the theme you are going for or not but it looks off (If you’re on another planet or something then it makes sense, but again we have no idea what you are going for)
let me update that real quick, the theme is zombies.
This lobby looks good, but it’s fairly basic. We also don’t know the details and specifics of what the game is about, so we don’t know what to suggest. Otherwise, nice job on it!
It just really looks very industrial. So, you know, it could use some life. 
Maybe take inspiration from movie that started it all; set your game in the farmhouse from Night Of The Living Dead, 1968.
To be honest, the lobby is fine, you made it classic, like everyone says, there are no ways to make it creative because of how simple it is.
I would only say that you could put some decoration of the style you mention, create paths (like carpets) towards the entrances.
