You have blown out highlights in a lot of the pics. I know that can be an artistic choice sometimes, but I feel the harsh lighting and blown out highlights (especially in your first pic) detracts from the content. For these kinds of shots, you typically want even lighting or shadows to create drama rather than blown out parts. There is nothing wrong with harsh lighting, it's only an issue when it's blown out.
Consistency in your backdrops is key as well. Your jukebox photos on down have some highly inconsistent looking backdrops that appears to be a lighting issue. You have a very distracting visual effect brought about by your backdrop. You also have a handful of creases from folds in the backdrop that are distracting. If everything was wrinkled, it wouldn't be an issue, but you have a small handful of major ones that stick out. I had a boss drill this into me in the past, but always always always be aware of your background. The background can make or ruin a shot.
Also be aware of how your backdrop photographs. That white backdrop in the HHKB and Jukebox photo creates some distortions at certain image sizes that is distracting. If you use cloth, either get something with a very loose weave (burlap, for example) or a very tight weave that doesn't show up in photos or that is so obvious that it isn't distracting.
The composure isn't bad, but it's not great either. I know I frequently have shots where I'm more concerned about content than composure, but since you asked for a critique, I'm giving it. Dead space is your friend. Learn when negative space can make for a more compelling photo. Work on angles and how to present something for the best effect. Mix those angles up. Get low, get high, get head on, get oblique. Play with figuring out different lighting for different angles and how to heighten the drama of the shot. Don't be afraid to get close and don't be afraid to get far away. The photo doesn't always have to fit the frame.