Is the iPad your own design or is it using one from somewhere else? Either way, you need to find a more options, layouts, perspectives etc. To add premium value to it.
It’s not just mock ups (but you are right send them as a set) - have a think about the iPad being portrait and landscape, maybe do a social post mock up for the books etc etc - it’s a fairly basic design so options that add value are essential
hi i think that u have several small issues indeed , the first one is as regard to shadows that look a bit too dark indeed, not being necessarily smooth enough , actually … i think there is a matter of harmony in the composition a bit , as things do not have a logics in my view and colors are also not completely matching , besides the symbol of this is what u have in the cover of the iPad which is not really super aesthetic or punchy. The thing is also that the positioning of the iPad looks a bit like it has been pasted there , that this is not completely integrated actually …