Secondly, your designs are plain and all I see are box logos. Like mentioned earlier, no one wants to buy an unknown brand. Maybe on your first designs, work on non-logo shirts but should have a certain feel to how you want your brand to feel. The key is creating an impactful design where you have people wondering where that shirt is from. When you start selling these shirts and your brand is being built up, then you can slowly start to push shirts with your logo visible. Hope this helps.
I think these are fresh, but the second one's the best. Maybe the design could be a little bigger and possibly placed differently.