Each of the new multiplayer units is presumably designed to meet a need, to fill a role in a situation or tactic where previously its race was weak. What situation is each of the new units designed for, and why couldn't similar Wings of Liberty units fill that role?
For example, Tempests are long-range aerial siege units that handle anti-air structures on the ground well, similar to Brood Lords or Yamato-using Battlecruisers. Void Rays lack the range to handle this, and while Carriers have the range, their Interceptors do not, so the Interceptors get shot down leaving the Carrier sitting there like a useless lump.
The Tempest is just 1 of the 7 new units, though. What tactical situations are the other 6 designed for?
