So, here are my thoughts on the matter.
Difficult to Invade
As was mentioned above, if you live in a hostile biome, then the environment is your first line of defense. The Dras don't have to be extremely powerful fighters who build massive defensive structures....because their home will kill most people who try to invade it, and all the Dras need to do is encourage this (fling diseased things into enemy encampments, for example). Not to mention that enemy supply wagons, siege engines, mounts, etc...are all just going to sink into the muck.
See also: Everyone who has tried to invade Russia, especially when winter comes.
Adverse environments may breed stronger creatures
The wolves of the far north tend to be more robust and lethal than the ones who inhabit easier climates. The creatures that can survive and thrive in a rainforest tend to be more lethal than those who live in a grassland.
If your tribe can tame these creatures, you now have lethal beasts serving as your weapons. (This may be a powerful advantage of the Kypiq, whose forests were inhabited by creatures so dangerous that they took to the trees in order to survive).
Advantages of being left alone
Because your territory is so hostile, so undesirable to other tribes...you are likely to be left alone far more often than races with traditionally desirable biomes (like the Neran grasslands). If you aren't constantly fighting battles and struggling to keep out invaders, you can focus inward on research and development. And on that note...
Adversity drives innovation
Who do you think figured out digging wells first? The people who lived in riverlands and had abundant water everywhere...or people who lived in a dry area where water was hard to come by? This doesn't seem like a huge deal, until you realize that wells are a critical component in surviving a siege.
Who figured out how to preserve food first...the people with a temperate, nearly year-round growing season, or the people who had long harsh winters where food was scarce? Again, we see a technology that is crucial to surviving a siege.
In short: adverse conditions drive a tribe to innovate to improve their quality of life and improve their chances of survival. These advances can easily turn into other useful technologies. The same knowledge used to clear a water road through a swamp can be applied to creating a harbor on the coast. The same improved tracking skills and techniques from living in an area where you must hunt all your food translates well to scouting enemies. The traps you develop to help catch your food can also be turned against your enemies.
Tribes who have an easy life because they live in an accommodating biome just don't have the same drive to innovate. That's not to say that players won't still innovate, but harsh conditions certainly produce more ideas for the sorts of things you should try to invent.