@Dogeek - curious if you guys have considered using
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instead of jpg/png to compress the images. It has lossless options if there's concern about quality and Ren'py supports it out of the box. Also there are
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if it's easiest to still work with the other formats and then convert them in a final "production" build. I know the game isn't that large yet, but I seem to recall there being mention of the expense around self hosting the game.