Today I've been messing around with ripping models and textures from the game, and it appears to be really easy to change textures. I did a quick test. 512x512 texture (about 5 minutes work):
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Since like no texture in classic eq is this big, it made my gpu fan turn on, so it's logical to assume a lo-fi texture pack would make things even faster.
I don't have the time or inclination to redo all the textures in game in an effort to make them prettier or high def (plus this was already done in luclin), but remaking them in a pixel/lofi aesthetic could be fun, interesting, and not that time consuming...