Speed Reload Versus Regular Reload
It bothers me how little difference there is between speed and regular reloads. In that the difference of time is almost if not always under a second. Realistically, one must put a magazine back in their rig, which takes a lot longer than the second-ish in between the removal and introduction of magazines in the game. The concept of the speed reload is to skip that delay by not saving the old magazine. With the game's lack of time for storing magazines, the time difference between speed and normal is a fraction of what I believe it should be. That's not to say that I believe that the difference is irrelevant; it has occasionally made the difference between success and failure, but that happens much less than one would think. It is my opinion that there should be a considerably longer period in between the phases for a regular load, thus making the speed reload more important. This should be especially true for machine guns, as you have to fiddle around with your backpack, with which most people would have difficulty without removing the backpack. As a balance to making speed reloads much more desirable in terms of time, it would require a greater penalty than just losing the last rounds in the mag. I would suggest that at a supply crate one would only be able to refill magazines that they have not thrown away, which would force players to think about their actions' effects in the long-run as opposed to the short.
Magazine Management
How magazine management works now is, quite frankly, boring. You reload and you get whichever mag of yours is the largest. It would add to the immersion if players had to actively manage their ammo, such as manually choosing which of their magazines they will load into the weapon. It would also be nice if backpacks had an actual use. I'd suggest that one would be able to store scavenged magazines in the backpack, but be unable to use them until they are placed in a chest rig's mag pouch. The same sort of thing should be available for explosives.
Weapon Switching
There should be a system that allows a player to switch to their secondary faster in the event of primary weapons running out of ammo. My suggestions would be one of two things. One, dropping your primary. Obviously, it would be faster to drop your weapon and draw your sidearm than to store your primary via weapon strap or whatever. Two, not actually storing the weapon. In this case, a player could lower the primary and draw the sidearm with one hand. This speeds up the transition, but the one-handed hold leads to worse recoil control, worse sway, and inability to reload. I am aware that NWI stated that they were looking into other underbarrel attachments and corresponding buffs, one of which would speed up weapon draw/store, but that's disappointingly simple for a game like Sandstorm.
Completely unrelated, but smoke grenades
This game has disappointed me as far as smoke grenades go. For one, smoke grenades (at least the M18; I don't have experience with other types) have a very satisfying "pop" when they start dispensing smoke. Smoke propagation in Sandstorm is also incorrect. The M18, after "detonating", starts spewing smoke out of its bottom. That smoke does not stay there; it's direction is determined entirely by wind. The stagnant cloud in Sandstorm is far different from reality. I understand in its entirety the reasoning for this in terms of game balance in a game such as Sandstorm, but like I said: it's disappointing.