That really looks nice!! Very well thought out and should be a breeze to load, operate and clean, nice job! Looks like you can get pretty good press force on the must with the length of the lever/handle, and as others have said, holding the pressure on mechanically would probably be beneficial.
One question, the back end of your handle attaches to a 2x4 sized vertical member, which will be in uplift force, how is that member attached to the unit? It’s hard to tell if it penetrates the table top and is fastened below to the frame, or just has L brackets holding it in place. If it’s the latter, that connection may be suspect.
Very nice workmanship, really like the looks of it!