Inventory cleaning time: I have copies of all the letters that My character read, such as Gorion"s letter, a letter to Tanzik, etc.
Should I keep them for any reason ,e.g., as to further a quest or solve one?
They are taking up room.
thanks, Muzzien

Unless you've got a quest to take one somewhere, I'd suggest stashing them so you can find them again later if it seems relevant. Those slots are better used holding extra ammo.

Put them in the cupboard in the kitchen of the Friendly Arm Inn (or the chest by the entrance). But no, there is no reason to hang on to them.

Virtually none of the documents other than usable scrolls or fetch-quest objectives are essential. Mainly they exist as background and lore information, and in some cases as clues for those not using a guide.

I can only think offhand of three exceptions, of which two are arguably "fetch quest objective" category -

* The book you're given to get back into Candlekeep later on in BG1 (but it's pretty clearly spelled out that you need to bring it, and doing so the next step of the main quest as soon as you're given it - unless you go on a sidequest binge, you won't be holding this for long)

* A couple of "papers" you need for guards to let you somewhere important in Chapter 7 in BG1 (I'm trying to be vague in case this is your first playthrough and you're not using full spoilers); again, you use these pretty soon after acquiring them (plus the item descriptions quite explicitly note that they're important).

* The scroll detailing the components for the Crom Faeyr hammer in BG2 (it doesn't just detail the components, it is itself a component and you can't craft the hammer without it).

Once or twice (IIRC at the ends of chapters 2 and 3) in BG1 you need to loot scrolls in a boss's room to progress the plot. but as far as I can recall the game never cares if you actually read them or indeed what you do with them afterwards.

Ok thanks everyone.Muzzien

As far as I remember in BG1 the quest letters/books that are important to keep have a warning in their description. Sth along the lines "This item seems to be very important..."