Tank is missing something, but what

My Asian tank is still simply missing something. It has so many hidey holes, all the back is covered with the moss, the caves, the nooks, the crannies and noone uses them.

Sure the panda garra will flow out of the rocks sometimes, but they hang out on the glass or around, looking for food. On friday I lost my mystery snail, not sure why, either it didnt like the temp drop or it was not having fun in all the rocks.

I dont think I have capacity for another fish, I have 30 adult white cloud minnows, 4 fry from previous rearing and now will be moving 9 fry from recent hatch. I have also 7 panda garra and the last sewellia.

I dont know what this tank needs, maybe some crayfish, some shrimp, something. Any recommendation? Maybe I am not seeing something

The tank is at 21 degrees now, dimensions are 110x45x40cm but the stones reduce the water volume. I previously tried paradise fish, bad idea, had many more sewellia, lost them and not going to tempt that again.

Frankly if nothing is going to be using the rocks and the piles, it is almost worth removing them, but I liked the design...

Your tank looks completely fine to me
But I think what's missing to your eye is some color
I think you should reduce the number of cloud minnows and add some some fish like
chili rasbora/ember tetra/cherry barb/neon or cardinal tetra
It's your choice what species
But also you can bring some more light to your tank by adding red colored plants like red tiger lotus,red cripts,Ludvigia sp. ,Rotala sp. if you have a rich substrate
But don't put crayfish they'll eat fish fry and even adults sometimes

Thank you! My light does not support red plants, nor do I have rich substrate. Regarding the color this picture doesnt show it, but for this exact reason I bought a group of normal colored minnows ,so I have a mixture of gold and the normal, which have nice purple hue. It did improve things a lot in my opinion