Getting married- 820?

Hi there everyone,

Here's the background: My fiance and I have known each other since we were children, so for 12 years now. He was my first boyfriend from 12-14, and then I moved back to Australia, so we were friends for the next 8 years. Long story short, we have been together for 2 years almost, and he proposed a year ago. He lives in Boston, and I live in Canberra. We are both 24 years old.

As I am in my final year of university, I am not planning on bringing him over until I have a solid grad job, and have sufficient funds and evidence (although I gather getting the evidence is difficult in long-distance).

We can only see each other about 3 months a year, but it hasn't been an issue for us as we are used to being separated due to the long distance nature of our prior friendship. Will this be an issue with immigration?

We are getting married next year, after I have graduated- and then we will wait until I've saved up enough money to start applying for visas.

Also, I'm thinking that he may want to come over on the ETA in the future and then apply for the 820. Is this okay?

I'm slightly terrified of providing the evidence, as not being able to spend much time together leaves little room for joint activities/assets. We plan on having a joint bank account once married, and I am documenting our mountains of phone records and emails, but I don't know what else I can do? I have friends that have met the both of us as a couple in Australia who will vouch for us, and my parents are very close with his parents- does this matter?

So sorry for all the questions, just sincerely lost.