Must possess is very subjective. Some people like NPC mods, additional people hate them.

This amazing mod for the Baldurs Gate 2 game adds a number of tweaks including infinite levelling, stackable potions, scrolls and gems.

Anything will be helpful.

• Useful Plot Items - version 1 Overview: This mod gives abilities to a few of the game's plot items which are kept at the end of their respective questlines, providing a slight bonus and giving them some more value. Currently the mod affects the Symbol of Amaunator, Shadow Dragon.
• EE has all the interface tweaks I needed, I don't feel a need for wide screen or bigger fonts. What version of EE are you running? Looks like some of the aTWEAKS could synergize to make SCS horribly difficult. I chose not to use the pnp fiends component, the one that lets each fiend gate in one more just like it. I kept everything else.
• The mod was primarily made because The Darkest Day fills all available kit slots, but players wished to use kits from other mods when playing it. Once the Mod Kit Remover has been installed, BioWare's kits will remain selectable and the mod kits will remain installed for use by NPCs and previously created PCs.