there is clearly an issue with perspective. What i spot is
- under the keyhole, you've got a patch of copper that has the same width all over the place. No matter it is in the middle, since the whole box shrink with depth, so should that patch.
- you draw all the wooden planks with the same height. Those that are further to our eye should appear smaller. You can (and imho should) also use "width" of those planks to suggest the shape of the lid better.
Btw, all i'm saying here assume that your chest is a parallelipiped box seen with strong perspective. Maybe that's not the case. Showing us the chest on pure side and front view could help us figure out whether we're working from the correct idea or not. You may also want to show us a sketch of a small room (just for perpsective sake. It doesn't need to be art) with the chest in, so that we can figure out how it would be perceived in its own environment.