CDI didn`t change much for me imo, added a bit of gas-response and about 10km/h higher top speed (as it sets the rev limit from +-8500 to +-9500).
Don`t know if it`s possible to mod the stock CDI for a `14 model. If you really want to: Just buy a `sport` one. Not recommended though.
The jetting mod gave me a good amount of extra torque, lets say about 20% more. The engine, stock, is just running way too lean. Downside being that you use just a bit more gas (but it`s fairly negligible).
The Multivar was the biggest upgrade for me personally, difference like night and day with acceleration and I even got 4km/h extra top speed!