In balanced view of aliens

1) They had poor SOP or didn't follow it by not scouting better ahead of
time. They had hubris working against them - they are colonial marines,
and no bug will mess with them.
2) The Sulako should not mount only ortillery that can be used 100km
from the unit - they need close support guns if they are that small and
that isolated. So yes they should have got support once they got
outside, but I think they wouldn't have much to shoot at - the aliens
came over in a tunnel and they dare not risk bombing the powerplant or
they die too.
3) Always leave 1 human behind on board.
4) Cashier sergeants who'll collect up all the ammo from their men. Or
not buck idiot orders from a newbie Lt.
5) Use the GUNS on the APC.
6) The minute you can't use your main weapons (10mm Saboted Light Armour
Piercing if I recall) or the grenades, or the smartguns, GET OUT. Do not
go further into the complex. You can't fight.
7) When your comms start to go, GET OUT.
8) Nuke the place from orbit (see the comment on fire support). Though
(sadly) the Sulako may only have been armed with class 1 and 2 bats for
defence, no ortillery. But I think it was meant to have some.
9) More Marines! Too small of a force to deploy by itself.
10) Idiots - don't land your VTOL on the site! Keep it hovering or at
least locked up. Keeping the ramp down.... sheesh. And having no
internal cameras in the VTOL.....
11) Sentry guns are great. Don't cut them out of the movie.....

The Colonial Marines were ego-loaded boneheads lead by a hopeless dolt
with a spineless Sergeant under him. Sigourney had more brains than the
group of them! But, OTOH, supposedly they were the best and rarely
tested. So arrogance might set in. The aliens were supposed to be smart,
dangerous, and oh so sneaky.

As for the cryosleep angle, we've seen that in the FT universe, that
would be the normal shipping method for Jarheads. As fish sticks. The
lucky ones might get rotated awake as ship's troops. But as a rule, the
mass ratio of 4:1 for an active vs frozen dude, plus supply usage, would
dictate cold sleep.

Anyone who plays traveller will remember the odds of not coming out of a
cold sleep berth.... <shudder>

All in all, I loved Aliens though. It was.... a fun movie.