Well, it would be nice to have a rough itinerary in mind; obviously you can be as flexible as you like.
Are there particular countries that pique your interest?
It might be good to head north after Italy, then south again as it cools off. And it’s true you will meet people and perhaps travel with them.

With that long of a trip I would make sure you are careful about your budget.  It sould be easy to run out of money pretty quick.

There is a certain romance in “winging it”, but contrary to logic, it could very well end up being more expensive than not planning anything. I’d love to do it one day myself, but it’ll have to wait till I have sufficient expendable funds to do so with any&nbspeace of mind

Some of the best travel-related stories I have ever heard – came from people (Europe or elsewhere) that simply “winged it”, not having a complicated itinerary, etc. 

Go for it, but go prepaired.  I plan on winging it for about a year starting this September.  I reccomend joining a hospitality community (like stay4free.com) so that you can make the best of your budget, and hitchhiking is a wonderful means of travel at least from the economical point of view.  Just hitch rides and see where you end up.  Though I have to tell you now that you need to make sure that you have all of your visas in order before  you plan on working or staying past the usual 90 limit in each country.

I was thinking a rough itinerary before leaving (rough at best)
As for countries of course i want to do the ‘big’ or main ones ie France, Germany (I might try and get to oktoberfest, I def know Some planning will have to go in to that), Spain etc. Also want to def see Croatia (Adriatic  coast) and Russia.
As for heading north first to be honest that would not bother me at all,  being from Australia the hot heat wont bother me at all, its actually the cold that will piss me off more  (for someone who has never seen snow, I think winter in london will be hard, but there has to be some downsides at some stages)

But its all still up in the air at this stage, but i value all your contributions.

You are on the right track of winging it, and using London as abit of a base, I would try and get your travel done in the warmer months, but at the same time you don’t want to run out of money, but you should be able to pick up casual work in some of the European countries, yes it is under the table but if it gets you into the next part of your travel, go for it.
If you do have to head back to London to find work, you will find plenty of bar work with live in accommodation, not the best paid job but it takes the hassel of looking for accommodation.
And with all the cheap flights from London, ie Ryanair and Easyjet, you can fly off to destinations for a couple of weeks and then head back and work for a couple of weeks
By the way, doesn’t really get cold in London until end January, I had warmer Christmas Days in London than here in New Zealand
Have fun
 

AU$9600 is a good start but it definitely won’t see you through six months, so you’ll have to work at some point. A lot of people tend to find a place they love along the way and just work in a bar for a month or so as they go, which is a great idea as it’s short term, you can be spontaneous and you don’t have to apply for – or waste – a UK working visa.
 
I would stick to the cheaper countries throughout July and August, as it’s the most expensive time of year (Eastern Europe, Spain, Portugal) and leave western Europe, the UK and Ireland til after the peak period. If you want to chase the warm weather, stay south for the months of October/November – Italy and the south of France are not only stiflingly hot in summer but they’re uber expensive and busy, so Oct/Nov is a good time to visit them.
 
In terms of winging it, I think it’s the best way to do it, although if you’re on a strict budget you might want to book some flights in advance, as the longer you leave it the more expensive they get. In terms of accommodation, booking a few days in advance online is probably sufficient, but if you’re planning on going to any festivals (you mentioned Oktoberfest), it’s best to book a long way in advance, as accommodation fills up quickly and you can be stuck paying through the nose.

If you’re from Tasmania, the North Coast or Aukland no problems, mate.