Resource Pack: Investigate why it takes so long to apply the pack after it's downloaded
I think this happens because there's a mix of 16x textures (including those inherited from vanilla) and 32x textures. When the pack applies, minecraft is forced to upscale all textures to 32x, which takes a long time. The connection will oftentimes time out before it applies the pack.
Somehow lunar client fixes this issue, but sepia says I can't force all of our players to use lunar client even though I want to.