The standard preset for size of image output is 512x512... but there are settings to change size (height and width separately) or to change the orientation with preset sizes, and to upscale as well as high resolution settings to get even more interesting and quality results. So, the size isn't a limiting factor for the quality with the Arty bot. That's the name of the main one.
I don't know all the specs about what resources are required to run the bot locally... but you could use the bot for a while and see if it's something that will give you better and hopefully faster results to achieve what you are aiming to do. I commend you on learning all that you have to make it this far in your art journey and applying the new technology.
When I have some time this afternoon or evening I will try and round up a few prompts for you to run on your setup and we can compare and contrast the results together, if you like. Is there anything in particular that you would like me to do theme or subject wise?
I am really looking forward to trying out the collage and digital arts while also supplementing the designs with some AI infused aspects. It's been a seed of an idea that's been germinating for quite a while. Fortunately, I have quite a bit of material already generated to draw from.
No, nothing special, you can choose what you like.