Provide a detailed and clear description of feature or change that you want to offer.
It would be rather nice to create a temporary and/or permanent solution to the Ring of 7 Curses' no-sleep penalty. I believe either an item placed in proximity to a bed, or something consumed beforehand should be implemented (of course, gated behind difficult challenges within the mod, like the rest of the penalty-nullifiers.)
Describe why you want this. If there's a reason.
Many mods use sleeping as a mechanism, whether for magics or for general purpose insomnia, and it is a nuisance to have a cursed player in a multiplayer server even with mods that require only a portion to have to sleep. Some way to treat this contained within the mod would be amazing, such as a dream catcher, or even warm milk, etc, would improve the total gameplay experience without making the game feel like the curse is non-existent. Perhaps a combination of a dream catcher, warm milk, and scented candles of a sort could help one overcome the insomnia curse? It's certainly something to think about.

I think I'll make it a potion.

I will think about how to best implement it, but at this point I agree there should be some way to overcome this curse, granted it takes fair toll. At least in the light of there being, as you already mentioned, many other mods that rely on sleeping as mechanic.

I think it might be good idea for it to be some sort of consumable or item with durability, as it will be completely disabling one of the 7 curses, so it shouldn't be permanent. The dream catcher sounds fitting, maybe craft it out of phantom membrane, some string and a diamond/emerald/something costly yet accessible early on, it could be a block that allows cursed players to sleep near it, and it could have a chance of breaking based on the times it has been used (Every cursed player that sleeps near it counts as one use), maybe it could go from 0% chance at 0 uses to 90% chance at 4/5/6 uses. You could also make it so if the dream catcher has been used breaking it will not yield the item back, and if the dream catcher breaks "your nightmares will become reality", which will spawn mobs around it based on the number of uses.

(Also, idk if this is already implemented or if it is possible, but you could add a config that allows cursed players to not be counted towards the sleep requirement for skipping the night)