Good day asgardian friends,
Here is how I see it,
Try to go into a Yve Saint Laurent or Ralph Laurent kind of style and not a GAP, AeroPostal Style.
I'm a Designer too, I don't like critiques but in the end I have to shape my ideas in ways that work for the public. After a while, you get used to it and you know what to do at such a level critiques become less usual and you are more intune with your audience.
T shirts great but Polo Shirts better, we are people that want to make clear to the would we are different, let's do it with style.
Try to use White, it's clean or Navy blue... Make the logo just the round thingy in bright yellow. Draw lines in the arms, one arm o the shoulders, like ranks from the AirForce you can also put stars. It shouldn't look printed but stiched or sewed.
On the back use big Negative color letters to write "Moderator, Asgardian, Engeneer, stuff like that just make polls to see what people would like".
Finally under the logo, that should be on the left part of the chest in small stiched letters you can try for "Asgardia or the initial of the name and the last name or the forum name once again polls are great for that".
If you do that make an official proposal and I think you might get a deal my friend.
Let me know if you need help, t shirts look good for a electronic music festival maybe not so much for an official Asgardian convention.
Keep up the good work,
Have a nice day.