I am not progressing too far until 2.3 is released since I don't want to have to start all over when it is released. And I have only played on single player so that may make a difference, not sure.
But based on my current experience, and the lack of weight being a factor I load out my squad with both long distance and short distance weaponry based on their skills and as long as there is room I provide them with medikits.
On top of this I provide grenades to the units based on their most likely positions, ie snipers and machine guns get smoke grenades, assault gets smoke grenades, frag grenades, and flashbangs.
There is usually one or two units that are pretty mediocre in everything except close combat and these I give smgs with flashbangs, smoke, and frag, plus the medikits.
The units with heavy skills which get the machine guns also get flamethrowers.
Assault can also use riot shotguns.
If the unit has HE skills then the grenade launcher is sweet.
I place the long distance weapon in the units hand and the close range in the backpack or holster so that when I first start out I have long range on almost all of my units.
I try to have 2 snipers, 2 assault, 2 machine gunners, and 2 close range. I use the Assault units to gain ground, machine gunners like mobile turrets primarily set on reaction fire, and snipers to pick off long distance targets. The close range units probe the buildings and act like scouts at times. I of course bring extra ammo.
This load out provides full versatility and plays to the units strengths. If any of the men get hit then there is normally another unit close by that can heal him. And if need be, most any unit can fill in for another, so if I have any on the wrong side of the map making its way to the hot spot I can usually use a unit currently at the hot spot to provide the function I need.
In this loadout flamethrowers are decent as they are only utilized in close range when they are needed, and the units carrying them also carry a long range weapon. Machine guns are decent because they throw a lot of metal around, and when you have a lot of metal flying, something is bound to be hit, just make sure your men in front of the machine gunners are not in the way. Problem with this is that flamethrowers are not always available since they are either acting as a turret somewhere or they have to catch up with the rest of the team.
I realize that once the weight restrictions become implemented that I wont be able to load my men up with so much firepower, but since it isn't at this time, I see no reason not to take advantage of the versatility that is provided by doing so.