I have theorized before that all Gateways lead to TAR. Notice how the weave Egwene used to enter the dream world was tweaked very little to give the actual Traveling weave. I think what happens is that you basically make something of a double Gateway when you Travel. The Gateway actually opens into TAR, and another opens from TAR into the real world. The space between the two TAR locations is actually contracted to nothing (since such things are possible in TAR).

Several aspect of Gateways reinforce this. For one thing, their size has less to do with OP strength than other weaves we've seen. This could indicate that Gateway size might partially correlate to your strength in the Dream, too. For another, to make a Gateway, you need to know your current location, or you can never use it. This is explained if the current location is needed to open a portal to TAR. Within TAR, porting to a new location is easy, and that's why you don't care so much about knowing your destination. Lastly, of course, the Dreamspike is something that blocks a region of TAR, and blocks Traveling in a corresponding region of the real world. That is very telling.

Now, if this is true, then the inconstancies over what can pass through Gateways is explained. Constructs are artificial beings into which souls have been brought in by human channelers. Entering into TAR might simply rip that human made connection. A human souls connection to its body is much stronger, so much so that hurting the "soul construct" that you make when you're dreamwalking can actually hurt the body. And since TAR can rip such connections between body and soul, this may also explain why the Wise Ones insist entering it in the flesh is wrong.

On the flip side, what does and doesn't enter through a gateway might actually be at the command of the person who makes it. It could be that the dimensionless space between the two locations linked by the Gateway is actually of TAR, and anything passing through that space would be subject to the rules of TAR. So the lack of strong winds could entirely be a result of channelers of this Age simply not wishing for the wind. One the flip side, when Aviendha made her first Gateway, she never knew about this, so she simply didn't think to prevent wind and snow from coming through. Same with Egwene when she opened her first Gateway into the Waste. She felt a blast of heat, and if heat can travel through a Gateway, so can wind. That it usually doesn't is proof that there is inconsistency in how this works, which can be explained by this being under the control of the individual channelers.