what do you expect from starcraft 2
i have some ideas
human
-allowing tanks to be mobile bunkers, allowing 2 marines to get into tanks so that tanks can have its own air defense, or 2 firebats for anti-zergling purpose
-bombers allowing humans to have strong air offensive power
zerg
-to build a special unit that can imitate any human or protoss unit in the expense of energy. for example it would take 1 energy per 10 seconds for imitating marines, and it would take as fast as 1 engery per 1 second for imitating battlecrisers. while imitating the unit, the unit can process the character they are imitating. However, terran can use missile turret to detect it and make it back to original form faster (the special unit has to use more energy to stay in imitate form), upgrade includes imitating one special units into 5 marines or 3 zealots, or imitating other units using less energy, however, imatiate SCV(or protoss SCV, forget what it cell) CANNOT build terran or protoss building. This unit will be zerg version of carrier, so it is going to be very expensive
have to go to class, more will come soon