I just can`t understand why do you need to switch to the SAME technology? asp.net mvc is ok. all you will get, while switching to python or ruby, is lack of typ

I just can`t understand why do you need to switch to the SAME technology? asp.net mvc is ok. all you will get, while switching to python or ruby, is lack of type system, generics, linq, f# power etc. it is big price, comparable to the development speed gain (???), cheap hosting (???), powerfull orm (???). If you want something really fresh, i think its better to take some no sql approach. or compose entire app on client with javascript. You can take all this modern things while using asp.net mvc. sory for my english.