Yamaha has really upgraded 2 stroke technology but uses it only on their snow machines not on bikes. Perhaps Husky's new 300 2T in 2014 will get them all thinking about this again. just watch the endurocross circuit or chk out the weekend warriors on Michigan single track. Many of them are still keeping or going BACK TO 2Ts
. Why not run a 200 KTM? It seems to meet all your needs and already has good torque.