Well, a couple of things, Drake...
The asura have managed to invent gates and golems.
Gates that allow you to travel between them moderately safely and, more importantly, instantly. Let's see the charr do anything of the sort. And the golems - asura are the only race able to create semi-sentient beings. It's just about the same as creating life. Also, let's not forget the asuran waypoints that everyone can use. Other inventions have originated from the asura genious as well, such as flight and even moreso levitation, refrigeration, and let's not forget GIANT LASER CANNONS. There's also holographic technology, weather-manipulation devices, generators, automated turrets, and you name it. Also, last but certainly not least, we have floating hammocks. Asuran sector's comfort by design!
Almost every asura invention is a massive failure, and tends to either explode or go horribly awry.
So does every charr invention until it's perfected, though it takes less experimentation to "perfect" the technology as it's so primitive compared to asuran inventions.
The asura rely entirely upon incantations and handwavium. If this was taken away, they’d become helpless and vulnerable.
Couldn't be more inaccurate. While magic is often incorporated into asura technology, there are plenty of inventions which do not rely on it at all. And even when it is, incantations aren't even involved. As for handwavium, or unobtainium as it's more commonly called, nearly all asuran inventions are based on common materials. To say all asuran inventions "rely entirely" on hard-to-get materials is factually incorrect.
The asura cannot mass-produce, so they have to contract out to other races to build for them (see: the new gate complex in Lion’s Arch).
Yes, because the asuran waypoints are so rare to come across, aren't they? It is more a fact of very few asuran inventions are made to be mass-produced. Waypoints are mass-produced, because they're intended for it. Asuran weaponry is mass-produced. Golems are mass-produced. All of these have a very high demand in great numbers. Asura gates, not so much - and asura gates are very easy to produce and assemble anyway, it's the tuning and powering that's the hard work, and non-asura aren't able (or allowed, for that matter) to do that.
They have no ability to work with anything other than stone, and rely upon the charr for their metals (they send expeditions to the Black Citadel to try and figure out how the charr purify metals, but so far have had no luck reproducing it).
This is funny because previously, they were only able to make their inventions with hard-to-find materials. Now they're only able to use stone. Does that mean stone is one of the rarest materials in Tyria? I smell something fishy, and it ain't a Quaggan. I would also like to point you in the direction of, for a very basic and obvious example, the electricity generators (yeah, so what if charr have almost discovered the secret behind it, we've been using it for ages), which use significant amounts of metal in their construction. And that's just one of many, many examples.
The asura have no true concept of proper scientific methods (only romanticised mad scientist nonsense), and merely use magic to ape scientific progress. Without magic, they’d be useless.
Again, as pointed out earlier, magic isn't used in every asura invention. Likewise, very, VERY few asuran inventions are based entirely on magic. In charr society, relying on magic is seen as a weakness, but in asuran society we harbor no such superstitious nonsense. Magic is a tool, not a taboo. Further, a scientific method is a process of systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses. Something asura excel at.
The asura have no concept of working together, and if you put three ausra in a room, you’d end up with one dead, one blind and dumb, and one swearing innocence.
Actually, if you get three asura together, you get four opinions. Source here, but may contain spoilers for Eye of the North.
The asura religion almost borders on scientology in how they’ve tried to actually turn science into a religion.
The asura have no religion. The Eternal Alchemy is an ideology, a philosophy, that everything is part of a greater connection and everything influences everything else. It is no more a religion than combustion engines.
And that’s what they believe in. This is what shows their lack of true intellect more than anything. If they had any idea of how proper science works, they wouldn’t be trying to turn it into a system of faith.
Again, there's no faith, no theology.