I have to be honest. I hate the actual opening process. Usually I am opening 20 or more figures at a time and it becomes very tedious. I guess I do take breaks because but it is to my detriment because stuff builds up fast. I have at least 7 5-packs sitting to be opened, 20 BATS, 10 cases of Desert/Arctic packs waiting to be opened. Not to mention I have the Fang/Claw wave of vehicles and a Rattler and Conquest to sticker. I hate stickering more than opening figures.
I find the BATS very easy to open actually. For the most part they are already in a good standing position. I just stick them on the stand and put the extra hand on the backpack. Next to BATS, Crimson Guards stand very nicely.
The real pains are the figs heavy on accessories or the ones that have quirks.
Snow Serpents are tough because they have a lot of accessories. I put the missile on the backpack and to do that I move the missile launcher stand to the other side. On top of that, the knee and feet joints tend to be really loose under the weight of them.
Vipers have weird ankle joints that you really have to work to get them to stand straight. The hands don't bother me and actually work well with the weapons.
Air Troopers are back heavy and tend to have loose leg and knee joints. They fall the most with little provocation.