Switching to spouse visa and path to naturalisation

[zerog]

Hello all,

Apologies if this is not the best forum. I am an Australian citizen studying medicine in the UK. I will graduate in June 2013, and I currently have a student visa that expires in Oct 2013. I previously lived in the UK as a dependent but not continuously or long enough for settlement. (I followed my dad who was later sent to Thailand and then Hong Kong - but stayed in the British education system)

I met my fiance 6 years ago and we have been living together for the past 2 years. She is a British citizen also studying medicine. We decided to get married ages ago, but we weren't in a hurry (we're both 23). However this week we just happened to look into the visa requirements and found they were a bit more complex than we assumed they would be. This left us with a few queries which hopefully the members of this forum can help with:

1. It appears that I first need a COA to get married. Some reports say it takes up to 6 months but I think that is rare. How long do most people have to wait for the COA? (We can't let the UKBA have our passports for 6 months at any old time)

2. If we then get married, would there be a problem with getting FLR(M)? Obviously neither of us will be working as we are both students, but I will have enough money to pay my tuition fees (this comes from my grandparents) and I have reasonable savings for my maintenance. My girlfriend receives grants and loans from the NHS/student loans. Is evidence of these funds sufficient to show that we can support ourselves?

3. After 2 years I believe I can get ILR. However my girlfriend graduates in 2012. The way the system works is you can get sent anywhere in the UK, but I will need to stay in London for my final year, and then I could get sent anywhere too. If I haven't got ILR by then, would there be a problem with SET(M) to demonstrate we are still in a relationship, since we could only visit each other once in a while? Should we just try to get everything sorted before this potential problem appears?

4. Can I apply for naturalisation immediately upon getting ILR (as in the next day)? I would have lived in the UK for 1 year on the student visa before getting FLR(M) for 2 years.

(you can skip the rest if not interested)
If you are wondering about my motives, well, I am just worried the visa prices will keep going up and the rules will change. I will need a PBS Tier 4 postgraduate doctor visa after graduating, then a Tier 1 post-study work which doesn't count for settlement (that's what my university said). After that then I can get a Tier 1 general. If we are going to get married and get the spouse visas anyway, why waste time and money on the PBS visas? Lastly my girlfriend wants to go to Australia, but not necessarily forever. The Australian spouse visas are twice as expensive as the UK ones, so we might as well do it over here, and if I had a British passport before we went then we could come back any time with no hassle or restrictions.

So in addition to the questions above, just in general do you think this this plan would work? Have I missed anything obvious or am I being too optimistic?

Thanks very much for any help.