Hi,
Yeah the inability to switch player models in game is a beyatch.
A sort of workaround for this that I have been experimenting with is to have a proxy unit that you can control in third person using the switchcamera "group" comand, and the squad order/cursor system (as well as some action menu items for fine tune control. you don't have direct first person control of the proxy "normal" unit, but you can make him go where you want, and then have an action to set up a sniper hide and get in your ghillie suit. When selected, the proxy is whisked away (with a titlecut black in/out to hide the transition) and the sniper player is setpos'd and setdir'd into position and you have total control again...
Not perfect, but it works well enough, and actually sometimes it is nice to have "your" guy crawl long distances with one click...
Versions of this will be incorporated into my fothcoming script based MOD in several manners.
-Grendel