The Cleaning Kit wouldn't necessarily change the gameplay in CS:S. It could even extend the subtle differences between CTs and Ts already present. The CT weapons are more professional, more accurate and quiet. The T weapons, on the other hand, and loud devices concerned with little more than getting bullets in that general direction. Compare the AK47 and the M4A4, or the Five-seveN and the dual Barettas. The Cleaning Kit could be expanded to a general Weapon Care Kit. For the CTs, it would be a cleaning kit with sight adjustment tools, whereas for the Ts it would be magazine clips for faster reload times.