Here are 2 features that would really be awesome to have added to the design tool.
The ability to adjust transparency.
The ability to resize WITHOUT constraining proportions. Leave the default to constrain proportions, so customers don’t accidentally destroy an image, but give an option to “free Transform.” This would be very helpful for things that don’t need to be proportional to look OK, such as a background texture, or even some frames, etc.
I’m very disappointed that Zazzle doesn’t offer the option to not constrain proportions!! Changing my image slightly will make it fit the product better, but that’s not an option. Hopefully soon!