You changed so much of the room, it's hard to see any of the lighting changes from the previous versions. The fixtures changed, the textures changed...
But I do see ambient light, and that's a good thing.
If you're going to use those type of lights, remember to put blocks with the fixture to create shadows on the ceiling. This is so you don't have just big circles of light on the ceiling.
Also, those lights don't project a cone like a spotlight. Pick a light range maybe similar or larger to the ones on the ceiling to use on the floor. the circles of light will overlap each other, and that adds realism because thats what happens in real life.
Remember... Follow the rules of the light source. Pick a proper light for the source, and for where it shines on. Repeat for every light fixture.
Don't try and guess where to put lights. let the LIGHTS decide where/how the lighting will happen!
Maybe start with a single light fixture in the middle of the ceiling. Get the lighting perfected on the ceiling and the floor. Then take the fixture, the lights and any shadow-making blocks and make them into a group.
An easy way to 'copy/paste' objects or groups is to select the object or group. Click and hold on the selected object... press and hold the SHIFT key, and move the selected object. This creates a duplicate

Place the fixtures where needed and the lighting will take care of itself AND look more realistic.
The realism of your room does have problems, and that, in my opinion, is due to lack of textures on your light fixtures. I can't tell they are lights that are 'on'. So visually, you dont have any lights that are lighting up the room.
You're improving for sure though!
Lights are the hardest thing to make look right. BUT they do a lot of work for you too and look great. I remember the first time i made a test room. Just a cube with default brick textures. The moment I put in a light or two.. i was super excited!
I was, like, This is EASY! And in some ways, it is easy. Fine tuning is a pain though. But remember, only YOU know how you want the light to look. If it's not 100% correct, only you know

And now that you know better the basics, you will learn that a lot of times you'll need even more lights, mostly ambient lights (unless you set the level's ambient in map properties). Sometimes you need 2-3 lights to make just one light look good, depending on the light you want.
But don't worry, you'll figure it out

I've always wanted to make a lighting tutorial, but don't have the time

So I hope this helps!
-Jason