Here's a simple little mod with a strange name by an author new to the database known as VMX. The CoD2SP mod offers a few options that are supposed to improve realism a touch without going "over the top."
1) This increases the ammo for all weapons to a reasonable amount, not the clip size, just what you can carry. This includes grenades.
Its not over the top, its completely reasonable for a soldier and maybe even a little bit more accurate depending on what point in the war you were in and who/what you were.
2) It also allows you to cook the grenades just like any grenade mod cook.
3) It also makes the weapon load out for each mission a bit more friendly. Its not UNrealistic. Its just a matter of "If I had my choice in this situation, what would I want?" ... those are the weapons you start with.