Best possible image resolution in this architectural view

Hello, I need this architectural story-explosion image in best possible quality. I’ve tried to render it on settings displayed on image HERE, but render crashed with “not enough CUDA memory” notification. Is there any kind of tweaking that can make this work and also look good? I am going to print it on poster about 30x55cm.
Just to have it written in here, my GPU is Nvidia GTX1050i

HERE is what it looked like rendered in 200% of resolution (plus color added in photoshop). If anyone have any suggestion about look of it I would also love to hear that!

THANKS

The message is telling you the graphics card doesn’t have enough memory for a render of that size.
If you have more system memory use the CPU to render it.