Can people request small mods to classes and items be made?

You can always post ideas. Whether or not someone takes up the idea depends on how modders are feelings. Historically, you have more luck getting your mod/kit made if you actually sit down and do it yourself. Everyone tends to have a lot of ideas they want to do and not enough time. Still, if it is something relatively simple to do or especially inspiring you might luck out.

Well I am playing a cleric of Mask in a tabletop campaign currently and I am digging playing a cleric with the same thief abilities as a rogue. The problem is that in BG2, clerics arent allowed edged weapons and cleric/rogue combos don't pack much like a true class rogue or cleric.

you can request it as a part of the next release of the divine remix mod found here http://www.gibberlings3.net/cleric/index.php

though i think the weapon restrictions are hard coded, maybe they could make it as a theif kit with access to the devine spells?

cleric weapon restrictions are definitely not hardcoded into the game as I've seen a couple mods that allow you to change them up. Ashes to Embers comes to mind, but I know I've seen others.