Swap the main weapons of the two classes or the ability (pioneer/medic).

Why the hell does the medic have an MG and the pioneer an MP? That makes no sense. The medic doesn't need the MG because he fights at the front, where he can get more kills and is more mobile with the MP than with the MG. And the pioneer doesn't need the MP because he fights further back and uses his MG to take people down and help others by preventing enemies from getting closer. And why the **bleep** can't my RPG... kill anyone with one shot???