We'll be doing a similar trip starting in FEb so I can't give first hand advice since BA is the only place I have already been. But in general, you're really moving around a lot. I definitely wouldn't add places. I would add the 3 days to those areas u mention in your post.

Thanks yestravel for your only response!!

Do you mind sharing your itinerary?? how long is your trip going to be??

This is a big trip for us and we'll be away a lot longer than u, so I realize u can't be quite as leisurely as we plan to to be. Here's a general outline of our trip. If u like big cities, u might want to spend a day or so longer in BA -- there is much to see and do in BA. Have u looked at Trip Advisor? Sometimes their forums get more action in SA than Fodors
Santiago - 3 days
Valparaiso 3 days
Chiloe 3 days
Lake Country Chile 1 week
Boat Ferry Crossing to Bariloche
Arg Lake District, - 1 week and then back to Chile
Puerto Natales and TDP - 1 week
el Calafate & area - 4 days.
BA 10 days

Piya, you have less than a full day in Santiago and not much more in Buenos Aires. November is a nice time of year weatherwise in both. I would add a day in BA if you can. Are you going to be doing mainly looking (rather than trekking) in El Calafate? Then your time there is enough. Well, one could always spend more time everywhere! .
You have Osorno there. You want to base yourself in Puerto Varas not Puerto Montt or Osorno, which is basically a business town. You can start the lake crossing from Puerto Varas.

Piya - A link to our blog with photos and our itinerary for Chile and Argentina where we visited some of the places you are considering- Entries #65 on cover Chile and Argentina:

http://www.travelpod.com/travel-blog/candcthai/1/tpod.html

We did not get to Glaciers (but really wish we had!). Loved the lake district and would have done the lake crossing into Argentian but it was not open at the time. the drive through teh lakes from San martin to Bariloche was spectacular (even though the weather was awful).

I feel you are shortchanging Valparaiso which I loved- a very quirky place, great for walking around and lots of interesting restaurants. Not so keen on Vina Del Mar. We only passed through on the bus on our way back from horseriding but to me it just seemed like an upmarket beach resort.

Not sure whetehr you are going anywhere near Pucon but we really enjoyed our few days there.

Thank you so much for your detailed responses. Suggestions noted...will make changes to my itinerary accordingly.

I'm not sure if Day 5 includes the flight to Puerto Montt but if so you won't see much of Chiloe (the ferry crossings will take two hours or more out of the day) when you get there and probably nothing of the Lake Disrict on that day.

This may be of interest:
http://homepage.mac.com/wasleys/sth_amer_08_mw/05_Pto_Varas/

You need more time in Santiago and Buenos Aires.

wasley -- have u taken the to ferry to Chiloe? What I have read has said, "The regular crossing service is from 7 am to 11.30 pm. The frequency is every 15/20 minutes approximately, and the complete crossing takes about half an hour." I have not read 2 hours for the crossing. thanks

@yestravel, Yes, we did a long day to Chiloe from Puerto Varas. The crossing took about 40 minutes plus say 20 minutes waiting = 1 hour each way, hence my comment about two hours out of the day.

The uncertainty is the waiting time. When we went there were long queues but each ferry can only take a limited number of lorries so cars and vans get called to the head of the queue. We waited about 15 minutes going (about 0900), 25 coming back (about 1900), much less than we feared when we joined the queue. Your experience may be better or worse. Additionally there is time taken to get to and from Chacao for the ferry to/from the island.

Once on Chiloe there is a fair bit of driving depending on where you want to get to. The main road which avoids settlements is quite fast but a bit boring. We set off down the ripio on the east coast which was much more interesting and we found plenty of places to stop and wander. However the ripio was not fast and in the end we gave up because of the time and headed for tarmac.

Castro had bad traffic going south in early afternoon and cost us quite a bit of time. Going north at around 1700 it was busy but moving.

You do seem to be cramming a lot in. We had about six full days to explore around Puerto Varas in the Lake District and Chiloe and found plenty to do, but then that approach suits our preferences.

The notes on the Facts pages in my site quoted above will give you more information.

Thanks for all your info...very helpful. we actually will be spending about 10 days in Chilean lake district. The OP has indicated less time there.

Sorry, I'd confused you with the OP when making that comment.

You can do vineyard tours out of Santiago and then you don't need to go to Valparaiso (which I would recommend). Spend more time in BA instead. I loved all my experiences in Argentina much more than Chile.