K, should've specified that their abilities would receive a correlating increase in damage/ratios/applied CC/etc. Basically, I feel that all the Assassin Carries are abominations. A DPS (damage-dealing, not just damage over time) champ should not get strong burst and strong continuous damage. I'm an engineer, and so I look at champ design as an engineering effort. Within engineering, specifically Aerospace/combustion science, there;s an inherent trade-off between the thrust put out by a rocket engine and how efficiently that energy is released. The more thrust (force) the rocket puts out, the less efficiently the energy of the fuel is used. I see DPS champs in the same light. If a champ has strong burst, they should be paying a penalty in the overall damage output (this is all ready the general chase, hence ADCs mattering more than Mages as time goes on). Giving a champ the best of both worlds make them immediately outclass either of the more restricted DPS classes that were subjected to that trade off.
*Edit, as to Yi, remember that "Jungler" is really a specification of where a champ is usually taken, rather than their role within the DPS-Tank-Support spectrum.