the length of the hilt will determine how much 'leverage' you can create with certain cuts. look at musashi's hilt length...it was insane long.
essentially in japanese sword arts (when dealing with two handed cuts) you hold your sword with one hand directly under the tsuba/guard and the other at the end of the tsuka/hilt, to make maximum use of this leverage factor while cutting. this allows you to draw the blade quicker across the cut.
like if you look at your standard one hand cut with a sabre you draw the edge across with one hand using your body motion to help the cut, on a two hand sabre you are also torqing/pulling with the rear hand to 'force' more speed resulting in a deeper cut...basically. it depends on the cut though, of course.
and dude, you would be set with a paul chen blade. of course they arent the best of the best but they are live and battle ready. a standard retainer of feudal japan would have been happy to take a paul chen quality blade into battle. the blades are good you may want to replace the fittings, but the blades are ready to go.