How about making the time it takes to get up after going prone take longer and make the stamina required proportional to the amount of bulk you have. That would stop people who run at you and go prone immediatly, shoot, then instantly get up and keep on running.
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<span style="font-family: Verdana; font-size: 8pt; color: #F5B800; font-weight: bold">"When one hunts monsters, one must be careful not to become a monster oneself—for when you look deeply into an abyss, the abyss looks deeply into you." -Nietzsche</span>
<a href="http://roguescript.hypermart.net" target="_top"><img src="http://roguescript.hypermart.net/lib/images/linktous/banner00.gif" alt="Infiltration Tactical Database" style="border: 0px solid #003000"></a>
<span style="font-family: Verdana; font-size: 8pt; color: #F5B800; font-weight: bold">"When one hunts monsters, one must be careful not to become a monster oneself—for when you look deeply into an abyss, the abyss looks deeply into you." -Nietzsche</span>
