When you finish throwing a grenade in Sandstorm, your character will always switch back to their primary weapon. This happens even if your primary weapon has no ammo and you've been using your pistol for several minutes. Having to then spend time putting your ammo-less primary weapon away and switching back to your pistol again can often get you killed. This adds a degree of needless risk and awkwardness to using grenades, and limits the flexibility of pistols.
The obvious solution to this problem is to instead make players automatically switch to the last firearm they were using before throwing the grenade.