Every char already has 16 inventory slots. 16*6=96
This is the same as in Baldur's Gate/Icewind Dale by the way:
I don't have to imagine some theoretical scenario of WHAT WOULD HAPPEN, because I know what would. I never had to ask myself, WILL I POSSIBLY take these healing potions or wands or that pair of extra weapons with me or will I pick up that magical breastplate to sell, because there's enough room to do that when you go out. I'd just constantly switch items between chars to not make them Overencumbered and if I was at the bottom of a dungeon and didn't want to go back to town the stacking, sorting and exchanging of items started so I could go on for a bit longer. You know what choices these usually were? Can I put these arrows into the quiver slot (even though this char doesn't use a bow) and save some space? If I identify those potions maybe I can stack them on those others and save some space. Let's put these items and/or useless vendor trash rings and amulets that will give a bunch of gold into the quick item and ring slots to save some space. Let's put this weapon I don't really need into the secondary weapon slot to save some space etc. Crafting items, letters and similar would end up in chests in some keep or local headquarter anyway till they were required. This and the inevitable trips back to town usually cost several dozen minutes and map transitions and added just that, tedium. At least a lot of action games at that point had discovered the use of the "town portal".
Getting the Bags of Holding in those games was a fucking godsend.
Anyway, you just have to untick "Don't Restrict Stash" in the game options and you can go on LARPing, since you can only access it from base camp locations then. Or as I said just don't use it at all and use the chests in your stronghold instead.
For me, it's one of the best fucking design decisions in the game as it spares me of the situations described above.
**** it lets be cool to hell with balance.