I do believe the traits are used to tweak the balance of power on special abilities. Not all abilities are created equal. Even still its not an exact science and there is some thematic reasoning behind the above values.

From your example above on paper the Thalan have the worst deal yet they always seem to be an absolute powerhouse in all my games and ive seen many other players make similar comment. I often use the 10 customisation points to tweak them more or less powerful (ie dumping the points into something less valuable or boosting their already impressive values)

I have a post in a thread somewhere similar to this, where I essentially ignored logistics and gave miniaturization higher priority.  As soon as I can find it I'll edit and link.

Here we are.

I notice you're neglecting to consider the free points that you have to spend on your own, which is not standard across all races.  Up until very recently, the Torians only had 7 points in DA, whereas now they have 8 both in DA and TA.  The Thalans are also hamstrung at 8, and this is probably a carryover from DA where they were a force to be reckoned with.

The bottom line is that both the Thalans and the Arceans get royally screwed in TA.  The Thalans get screwed for tech tree, too.  Did I mention they also get screwed for SA?

Silphius, they're a "powerhouse" because they have nothing to build, so they build ships.  The AI also likes to rush buy things, so the issue of colonization speed is not as much of a handicap as it is to a human player, although the AI does run a larger deficit longer.

True, and true.

However, even by my own math, the Altarians aren't that bad, at 18 points total, even including the weapons malus.

And, again, it all depends on how you play-the Korx have an equivalent of 26 points in my book, or 31.9 in DA, but it doesn't help when 18 of that comes from trade and trade routes.

By far... the Altarians are the most powerful race in TA - if only by their tree advantages.

Lemme fire up Galactopedia here for a moment to give, IIRC - a few more examples;

1) DarkEnergy research.

2) Nothing else!

Get techs much faster, you are ahead in most key areas unless you use the cakewalk driven agenda gimmick that the *NoTechBrokering* option truly is.

But, DA has much different balancing considerations for them to be at least up to where Korath can become. Don't start me on the Krynn, though.

Yep, but i'm still a Pacifist who hates Evil tactics no matter how many better ships they can throw at me. If i've got matching defenses soon enough to NOT be conquered. Besides, i can organize a beelow Hive, can't i?

That Neutrality is indeed a *VERY* sharp edge -- How many times have you seen them keep it though?

Storyline wise i would agree, but while my Altarian ass is being kicked off a pretty much tied Influence race, should i bother worrying about how Peacefull i am with 100+ more ships in standby than they send at such key moments?

Hivers screw the wreck of a mid-game - but once they leave their tight area of Space, they *normally* (all things being relative for anything other than THE Conquest Victory) scream for help at peoples already under my thumb.

Let's call this a tie & a gambit by necessary erosion(s), shall we my friend?

The Altarians' offense can end up being formidable.

I was trying to play them peacefully, and got attacked by the Drengin, and then the Yor followed. I convinced the Dratha and Terrans to help against the Drengin, but then the Dratha inexplicably declared war on me after the Drengin and Yor surrendered their empires to them. Fortunately, I was way ahead in tech, so I started to crank out Large ships with a couple missles and a few impenetrable Telepathic defenses. These single ships were taking out whole fleets without a scratch.

I invaded all of the Dratha's planets, then took out the Arceans for good measure (they had 2 planets). Meanwhile, a minor race appeared on a planet in my home planet's system. They lasted exactly one week. Free high quality planet! Thanks!

With 90% of the galaxy under my control, and only the Terrans left (shaking in their moon boots), the 'good' Altarians won a cultural victory.

-Iconians get two extreme world techs.
-Yor get one extreme world tech and the single most annoying effect in the game: In their space you can only move 3pc/wk.
-Korath get one extreme world tech, and the ability to turn any world they attack into an extreme world...that they just so happen to have the tech for...and they even get to ignore population and soldiering while doing so.

By any account, the Iconian SA is subpar; mediocre and highly situational at best.  To attempt to compare either of the above halves of the abilities of the races in question to another 1k base research saved (multiplied by tech speed and galaxy size [larger = costs more], such that it's oh about 600-660 on a gigantic on very fast) shows you exactly how badly the Iconians got screwed.

Their tree is somewhat interesting in TA, but it does not differ from the Yor significantly enough to be worthy of merit, apart from their repair bonus.  You could say the farms differ, and the Yor do get an interesting method there, but I wouldn't call that enough, nor would I weigh it in the favor of the Iconians.

What difficulty?  While I'm at it, what galaxy size?

1000 tp tech, Very Slow:
Tiny: 978
Small: 1009
Medium: 1040
Large: 1121
Huge: 1206
Gigantic: 1303
Immense: 1355

Also, with regards to my above post, see how much better you'd do using Isolationist or Annihilator (mostly Isolationist for the colonization stage).  Granted, in my experience (and YMMV), barren worlds aren't quite as common as the rest, but it's still generally worth the other half of the ability.

And how did you fare before TA brought you that option? 

I've played both the Yor and the Iconians in TA, and I find the Iconians much more my speed.  Their manufacturing and research in the early game is phenomenal - if you can get your economy in order, you can be off to the races no prob.  The reason for this is due to the efficiency of Replicator and Interstellar Refinery buildings, with the accompanying efficiency of the research buildings.  If you can find multiplier tiles, that efficiency goes up even more.

Also, their Organic Hull Plating technology is incredible.  Assuming you can trade out for even second rate weapons tech, you can get together a killer navy at the Small and Medium Ship stages just be relying on plating and HP plusses for defense.  The Korath Annihilator ability and the Yor Isolationist abilities are definitely stronger in and of themselves, but the packages aren't quite so lopsided taken together.

Sole Soul:

If you read the entire thing, you would note that I agreed that the SA's taken in isolation were as you supposed.   That said, if you haven't played any of the stock races for a long while, how can you confidently make assessments on their relative strengths, all things considered?

In TA, the Thalans start off with the ability to build some powerful GA very cheaply.  These make the homeworld a powerhouse and as long as the Thalan can expand quickly, with this superb headstart they can be a force to be reckoned with.