Ciao
Everything can be done.
We are also italian and we did that route 2 years ago [wow! it's already 2 years...time goes fast!

]...
As already said:
No border open between
Armenia and
Turkey so you'll have to go trough
Georgia.
It is better to get your
Iranian Visa in Italy, the Consulate in Milan is in the very center (so you get to see the Duomo

, and the Visa will have 3 months validity from the date of issue (this means you can enter in that time frame and from there your 21days/1 month visa will start).
I don't know wether you need a guide or not, we didn't have one, but maybe things have changed.
About
Pakistan I can only suggest you 2 things:
- don't ask it in the Consulate in Milan
- tell them you are going via airplane (showing them a airplane ticket if necessary)
When we went there in 2011 telling them we wanted to ride from Italy to India, they simply refused to give us a visa. It took us days (and the help of the super nice secretary) to have a meeting with the Consul so that we agreed that we would ship the motorbike straight to Islamabad from Dubai in order to avoid driving in Baluchistan. (They gave us a restricted visa to make sure that we would do so).
☆☆
Read the story on our Blog ☆☆
In 2013 on our summer holiday to Italy we went back to the Consulate asking for a new visa (why not?

)and after a first refusal and a funny attempt to ask us a Piece of Moon before they could proceed, we got our Pakistani Visa valid for 1 year from the date of issue!!! :

:
[See you in Pakistan in July!!]
Papers needed: an invitation letter (if you check even on the hubb there are some travel agency that can provide you one).
The Piece of the Moon that they wanted from us was an invitation letter from a governative authority, possibily a minister. Well, we got one from the Pakistan Tourist Departement that stated that we were gonna go to Pakistan "to promote adventurous sports"!
For
India no Visa at the border.
If you want to be sure to have a 6 months visa you should get it in Italy, but consider that Indian visa start from the day they are issued (not from the day you cross the border).
In 2012 we got 6 months visa in Islamabad (not so easy). Since then only 3 months visa (both in Sri Lanka and Nepal).
☆☆
Read about the Indian Visa in Islamabad on our Blog ☆☆
A veichle can stay in India for only 6 months on a row, then it has to go out (same for Turkey).
Nepal: visa at the border 25$-->15 days, 40$-->1 month, 100$-->3 months
Best time to visit Nepal is spring (april-may) and autumn (september-october).. so Enjoy!
About the rest of SEA... we got stuck this side of Burma (we spent 2 years between India, Sri Lanka and Nepal), we will try to cross it in the summer of 2015....
Write us a email (in italian

) for any other info..
Buona strada!

Agata and Thomas