It is generally a bad idea to use 2h weapons in their 1h mode. They become extremely slow and have very low damage. If you do want to go through with this build, I highly recommend using one of the following instead of the heavy bastard:
Langes Messer
Fighting Axe
Military Sickle
These are all classified as 1h weapons, and as such receive no penalty when used with a shield. In addition, their secondary mode is 2h, which grants additional speed and damage.
Hope this helps!
Edit: Take a point out of shield and put it into athletics! Quick footwork is going to be essential, especially if you are limited to short weapons (which all good 1h/2h are quite short)