Game Models - how small can I paint and scale UVs?

Currently working on improving my efficiency when it comes to my UV and Texture maps, since I am gearing up to work on some mobile game assets.

Additionally, I have been reading up on how some of the old game systems went about doing this, and I stumbled upon a really nice article that covers some of the techniques used within Wind Waker. This has then led me to analyzing some of the old nintendo game’s texture sheets and models, and I am amazed at how they were able to decrease their overhead.

On to the question.

How small can I feasibly paint my texture images and proportionally scale down my UV islands before running into any artifacts/quality loss? The goal: fit as much onto a single texture sheet as possible.

Up until now, a lot of the texture images I have been using have been around 2k by 2k, and I have been painting on them fairly large. For better or worse, I have been able to use multiple images for different parts of the meshes, but this is an easy and lazy cop-out to ignore UV overlapping and whatever loss in performance has been nominal on other projects. Now, it isn’t going to fly with the next few projects.

What are some best practices regarding image size and UV scale? If there are any tutorials that potentially cover this, I’m open to exploring whatever I can. I havent really found anything about performant layout et al.

A few of the referenced links to Nathan Gordon’s posts (Thought they were fun reads and learned some shtuff):

https://medium.com/@gordonnl/fire-and-haze-b4561743b17 - The size of the flame sprite sheet appears to be no larger than 32x32 pixels. It is effectively a particle.

https://medium.com/@gordonnl/links-expressions-eb7beae2c62c - Link’s texture appear fairly small as well. Images shown at roughly 2/3rd way through page, but I have also been looking at a model posted to model-resource.