If you leave numerous things behind it's like saying to him "I have no life outside of here, and it's not important for me to take care of myself when I'm not with you.” That is not a message you want to project. Not only are you presenting yourself as needy, dependent, and insecure, but you might also be reading a lot more into the relationship than he does. After all, if he wanted you to move in with him, he'd just ask!
It is okay to leave one or two things - perhaps your favorite robe or pillow that might be too bulky to travel back and forth. Otherwise, get yourself a nice travel bag and pack it up when you go home.
Making the commitment to live together is a decision you both have to make. You can't make it for the both of you. Stop leaving reminders of yourself behind. Instead, don't leave anything and let him miss not having you around. If he misses you enough and wants to have more of you, then you can have a discussion about the living arrangements.
Once you move in, you can demand all that space for yourself. Go ahead and ask for two drawers if you want!