Last time I took a look at it, I don't remember feeling like it was the Traveler in particular. Let's compare notes.

Working from the completed image I see two main mysteries: Who / what is The Speaker, the one who's words we are reading, and who / what is The Subject they are talking about.

For The Speaker I get this:

1. Someone who is able to observe The Subject , either by staying near it, or viewing it from afar.
2. Someone who is able to discern The Subject's intentions, and emotoins. Perhaps by direct observation, or indirectly by picking up broadcasts.
3. Possibly someone who is able to exist for a long time. The events (almost certainly terraforming of planets and moons) seem like they would take a while even given a fantastic level of technology. But that's pure speculation, it could have been quick with all the planetary events happening the same day…
4. It believes that the best voices never allow themselves to be heard.

There just isn't much to go on for The Speaker. It doesn't ever refer to itself, and that's pretty much that.

We have more information about The Subject:
1. It can use its voice to urge, but only a trusted few can understand it, whether by design or not.
2. It wonders what happened to once populated places.
3. It seems to have a past that it doesn't remember / understand, "You draw deep inside, seeking direction, truth… But all you have are the riddles of your own intentions" The Speaker comments about it at one point.
4. It is looking for answers, and wants to tell everyone that it is strong again.
5. It has the power to terraform worlds and the attention to detail necessary to closely watch the process.
6. It is apparently a builder of worlds that leaves when it is done.

In some ways I want to believe The Subject is one entity. But it occurs to me that perhaps The Speaker is speaking to each of the planets in turn (thus my rampant speculation and interpretation):

1. It tells the Moon that it is best to be silent, that it has great influence, but it doesn't anymore
2. It tells Mercury that it used to be a livable world but something destroyed it, something from the past that has come again
3. It tells Venus of its terrafroming, and notes it’s confusion about its past… though the text seems to be speaking to something other than the planet (Venus) that is being described…
4. It talks of the Sun watching reemerging, and wanting to badly to spread the news.
5. It talks of Mars being terraformed, and again seems to speak of the Subject watching from a distance.
6. It talks of Jupiter (or perhaps its many moons?) being pushed into position.
7. It talks of Saturn being moved and its atmosphere boiling away, and it seeing and being seen (by the stars?)

I don’t know. These bits of text are confusing and mysterious and so open to interpretation. I feel confident that there is an unknown Speaker, but what it is speaking of sometimes seems to be of the planets themselves, and sometimes of the Subject who created / terraformed the planets. If anything is The Traveler I’d say it’s the Subject, traveling between planets, looking for answers, and recognizing its past works. But that is of course very tentative and undefinite.

But I also feel excited, and hopeful that this is a coherent and solvable mystery… We may not, probably don't, have all the facts we need yet.

I don't think you're correct. He said

Second, because it's so much better, the game has to be balanced around purchased weapons.

That seems to mean that he thinks that the gear is actually BETTER, not just easier to acquire. I don't think that's true.

This is how I read it:
Due to the statistical unlikelihood of receiving ideally-balanced gear of epic quality through normal gameplay, the only way you'll generally be able to equip those items is to purchase them on the Auction House. While it's true that you could acquire any specific item through normal gameplay, the chances of that are so incredibly thin that it's generally not worth the effort to grind for it.

Even if I did find an item of "epic" quality, there's no guarantee that it would even be balanced for my particular character/build. But one man's trash is another man's treasure! My best bet, then, is to post that less-than-ideal item to the AH where someone else can buy it, and then I can use that money to purchase something that is more ideal for my character.

In this sense, a piece of gear from the AH that is tuned for my character actually is better than what I received from the in-game drop. For better or worse, this is how D3 is designed. When I played, it certainly felt like I was being forced to the Auction House even though I didn't want to use it, and that left me with a bad taste in my mouth.

Huh. I never played Diablo 3, but I actually discussed this model with someone who did not too long ago, and I was under the impression that the stuff in the auction house wsa the SAME as the stuff you could get through drops. As in... you could play for it, or buy it.

Maybe I misunderstood? (Or maybe you did - sounds like you haven't played it either.)

I believe you're right, but that implies stuff one would have to grind for are readily available in the auction house, granted one has enough money. If you didn't have to grind for them (i.e. if they were very common), the auction house would make no sense. I think that's the point he was making.

I don't think you're correct. He said

Second, because it's so much better, the game has to be balanced around purchased weapons.

That seems to mean that he thinks that the gear is actually BETTER, not just easier to acquire. I don't think that's true.

Yes everything in the auction house drops, but so infrequently most people will never see anything that good unless they farm. So when you go to the auction house, all the gear is better than what you have unless you have no life at all and can do gear runs, because people only sell good gear! Nobody is going to want to buy bad stuff.