Have to say I don't really think much of this material from the sources you are providing, seems like a lot of EU, and low grade EU material at that. As has been said earlier, not too reliable. I don't consider anything from those Empire at War/Force Commander etc type games canon in any way shape or form.

The first and most reliable source you provide is from the Star Wars databanks, and that seems to say that pretty much all the Rebel ground forces seen in the movies are SpecForce. In fact the entry is for Rebel Trooper calls them SpecForce, and then splits them into specialist classes. From this discription it would seem to be saying that all Rebel Troopers are Special Forces, which if you think about it makes perfect sense. This isn't a war where you have equal sides that can throw the same amount of manpower and material against the enemy. The Empire far outmatches the Rebel Alliance in terms of numbers and available assets. Only in the sort of games I mentioned above would you have Rebel forces going toe to toe against Imperial ground forces of equal measure in a conventional World War sense with front lines. This would be a total fiction in the Star Wars universe. The Alliance was outmatched in every way and used hit and fade tactics in space and on the ground, more akin to guerilla warfare.

So with that in mind a Rebel Trooper had to be worth 10 Imperial Troopers, this wasn't always the case, but you can imagine that Rebel Troopers would be trained to become a more survivable asset as they would be a much more valuable asset to the Rebellion due to their small numbers than Imperial Troops were to the Empire since they had an endless suply of cannonfodder check out the design of the TIE Fighter for proof of this doctrine.

So I guess what I'm saying is I reckon our current set up for Rebel personnel is pretty sound lore wise, though I won't deny the fact that our desert cammo troops are simply the forest gear troops with the colour changed for ease, and to be honest that works pretty well. Our Rebel Fleet Troopers are akin to Marines or fleet security as the Imperial Fleet Troopers are for the other side (though we have used him as a Support Trooper).

On Yavin 4 during the end ceremony you mention we see a lot of troops in khaki uniforms and similar helmets to the guys on Tantive IV, we see a lot of these guys in the hanger also and they seem to be technicians mainly, though this could also be a general uniform or dress uniform, or fatigues. At the end of the day the Alliance is a rag tag band of troops and militia that are going to have various types of gear for different needs.

So anyway I guess my argument here is that all Rebel Troops are SpecForces due to their small numbers and survivability. So in any encounter you are going to see them in one form or another.