Recommendations for image size and quality in e-learning courses - Articulate Rise

Hello everyone,

I am currently having an external graphic designer create illustrations (individual personas) for our e-learning courses and I have a question about image size and quality requirements in Articulate Rise.

Do you have any recommendations or guidelines on what file sizes and qualities would be optimal for images, especially for use in Rise? I often have the problem that illustrations in very good quality are displayed too large in Rise, but as soon as the quality is lower and the images are displayed in my desired size, they sometimes look blurred. If there are any specific tips or documentation on this, I would be happy to pass them on to the graphic designer (e.g. export in size X from Illustrator). Perhaps there are contributions from Articulate or similar.
I know at least that SVG & PNG are the best choice, but I don't know any concrete size specifications.

If there are any helpful links or guides, I would be happy if you could send them to me as well. You are also welcome to forward the question.