Some modded server hosting websites allow custom modpacks through the use of twitch/curse's 'export profile' button which can give instructions for what mods to install on another system. Incorporating this system onto your website would allow people to upload their mods directly from curse without having to manually install 100+ mods and without having to worry about which mods your website does not support. The one thing I beg is that you don't lock this feature behind a paywall. In doing this, you will turn away potential customers who would instead be happy to use your service over another website's.
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