As far as the vision goes, we really do not know how well they see without the mask on their home world. It is possible they can see without the mask, similar to ho we see, but any number of things could have been interfering with the P1 Pred's vision.
For some unknown reason they can breathe our air, for at least a short duration of time, over half an hour at least, but it may not be ideal for them.
Poor breathing can have all sort of detrimental effects on humans, and it could be different in how it affects Preds.
The result of poor breathing for them may be blurred or even single color (red) vision without the mask.
In P2, when the Pred is mask less, it is seen breathing through some kind of filter, "sucking air". Our air maybe just barely breathable by their standards.
Every time a Pred Mask is taken off, the tubes that connect it release some kind of gas, presumably what the Predator is more comfortable breathing.
Seeing how the conditions in which we saw the Pred's vision in P1 were not ideal, we cannot assume that the Vision of this Predator under those unusual circumstances was the way the species sees under more optimal conditions.
They may very well see more similar too us, and it would simply be the technology in their masks that allows for other vision modes, including the typical "heat mode".
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So now that this is out of the way, I would imagine their home world being in a hot environment. Or the climate may vary there as much as it does here.
Seeing how they are very strong, and powerful physically, while they are intelligent actually gives a few key insights into what their culture would be like.
There are some parallels that CAN be drawn off of the way they are built for example, is an indication that physical strength gives them a reproductive advantage.
It is at LEAST true of the males that they would compete via hand to hand combat where physical force is needed to get a mate. That is IF we can even be sure at all that is the gender we have seen, or even if they have genders, more on that later.
I could easily see a culture with an event on their home world that parallels Gladiatorial games. The stronger of the male is the one who gets to reproduce with said female. Love may not be a part of their culture at all.
Females may deliberately chose males based of their physical power/ hunting skill/ fighting skill/ bravery/ etc... as mates.
Then there are of course brutal coming of age rituals to even more-so ensure this. Only the most fit will survive their first true hunt. That is assuming the killing a Xenomorph is even their first hunt, this could just be a ritual of coming of age to reproduce, and they may have earlier been allowed to hunt other things. It may be an option, taken on by Predators that want to be considered the elite.
We really just do not know, but we can safely assume it is some sort of "rite of passage" that intends on only the best surviving, and the less fit to be removed. In this it makes most sense that it is for a "reproductive privileges ritual".
Back to the Gender idea. The only way to know for sure if the individuals so far encountered are even male is to know what reproductive system they use. For all we know they could all be hermaphrodites that lay eggs.
Or if there is a 2 gender system, then the smaller might NOT resemble a human female at all. It is possible that she could, but it is every bit as likely that the females are put through the same tests as the males, and even have to compete with their own respective gender in combat to reproduce.
I do not see them as a species were males select females based off of softness, elegance or beauty the way humans do.
Human males would most often rather select a female who is physically weaker than another female when the weaker one is prettier. 5'3" 108 pound tart with round butt-cheeks and c cup breasts is FAR more attractive to MOST human males than would be a 6'3" 225 pound woman with a massive lower Jaw and big hands and feet, small breast and a big nose. Human logic would consider the latter an "ogre" woman, and the smaller one "hot".
Which logic makes most sense to a Pred? Obviously the bigger more powerful female would produce the strongest offspring, therefore is a superior option to mix their own genes with.
By this logic, it is more likely that Predator females may actual be as big, quite possibly BIGGER than the males! They may not even appear female at all to us, or may only show secondary sexual characteristics like breasts while caring for offspring early in the offspring's life, and once the Offspring are no longer being breast fed, the breasts may shrink back down to not even being visible, and again the female might just look like a male.
That is just IF they even breat feed at all. The young may be born ready to eat meat, and the females may have no secondary sexual characteristics different from the males.
IF they even give live birth, it is also possible that their young are a far smaller % of their adult size when born. 2.2 pounds or 1 kg, or even smaller. They may just grow rapidly.
Females may not even rear the young on their own, and the young may be educated collectively by an appointed "teacher(s)" and in groups, who may be a trained by a retired elder Pred, or one that has lost a limb and is no longer hunting, and now is given the job of "teaching to hunt" as well as all other things Pred, which in its own way is an honorable position.
Then again, we can not say for certain than Preds cannot Re-Grow lost limbs. They may not re-grow it overnight, but perhaps after several weeks they get a new one? No way to presume they cannot.
We could assume they live much longer than us. I still would not be shocked to find out that they do not however. It is possible that the old gun at the end of P2 had become a Pred Heirloom, and was not itself taken by that particular Elder himself. I still think they live to be many hundreds of years old, but I just think it would be unwise to not keep all options open.
Now what would the bigger part of Pred society be like?
I just cannot see Preds bickering over much the way our Society does. We tolerate a LOT of things the Preds would not.
Given their aggressive, die or die trying mentality, I find it VERY unlikely they put up with any crap.
At some point in their history several factions tried to make their way of life the only way of life on their world, as has happened several times in human history, the result for them would be different than it is for us.
Human conquest is always, ultimately halted by another human faction, or too much compassion from within its own ranks, or some of both. Genocide in the name of a "one world order" is just too much for most humans to stomach.
I doubt that is so for the Preds. When in their history any faction tried to take over the world, or several of them, they would just continue to fight it out until the strongest faction became dominant. Period. After they fought it out, ONE supreme faction lays down the laws and how everything will be. The losers are killed. Callous but simple and effective.
Think the Preds have elections? Neither do I.
Think that any powerful Pred ruler would ever tolerate another alpha Pred calling all the shots? Nope.
I imagine that to them, the most logical choice, in their brutal way of thinking, is that there is one supreme ruler over all the others. Now they may have a relatively militaristic society, but I think that ultimately there is one Pred in charge of all of them.
An analogue to what humans would call an "EMPEROR".
I doubt it is a hier position, and is quite very possibly fought for, hand to hand, to the death, when it comes time to replace the emperor when he dies. WHo knows? he may even have to fight to retain his position regularly as well.
At the very least I would think they would fight over who gets to take over when he dies from age, even if he does not fight to retain his position.
This way only the strongest rulers will carry the torch. Because we do not know about the gender system, they may have an Empress instead, or both, yet I doubt the last option, as monogamy does not seem like it would be fitting in their culture.
Any how, this is all conjecture, and we really do not know anything for certain. These are fictional creatures, so I hope my ideas on them have not pissed in any ones Corn Flakes.