I like this. Can be a super t-shirt design. Create a better presentation. Don’t ode that splash around image. Use a t-shirt mock-up.
6 years joining invato none of my designs are accepted 
, I use corel draw x7 to design, remove the gradient effect to make it look flat, there is no open curve and every time I send work I don’t forget to include the font type and the link. I am confused if there is something wrong with my design. 
Doesn’t meter what software you use. You have a very good item and you fail on presentation. Personation is the only way to impress the potential customers.
I recently I have applied at Envato, and I am good at PPT’s and PSD’s, even I tried my best to submit one of my most best ppt stuff I have made,
but got rejected. but I’d like to know clear reason, like what exactly we have to made and submit,
well you need also to find perfection.
BTW I personally liked your design.
