Income Protection, Trauma and TPD Options with Mental Health History?

Hi everyone, Looking for suggestions regarding super options and IP/TPD.

I am self employed and make about 80k per year, my wife makes about 50k and we are expecting our first child.

Currently I have default cover through MLC at $15.29 per month for 273k life, $13.70 per month for $273k TPD ANY occupation, and income protection at $6.83 per month for $4150 per month with a 2 year benefit period. So

In ideal world, I am hoping to get coverage of about the same amount to supplement this, but with TPD OWN occupation definition, and income protection of about $4150 per month to age 65. I'd also like to get Trauma and Critical Illness for about $100k.

Here's the catch. I have seen psychiatrists on and off for mild ADHD and mild depression throughout my life, most recently being November 2018. I have seen psychologists on and off, most recently being 2017. Haven't had any treatment or symptoms since then, managing things ok for now.

I spoke to a broker last year and was offered coverage with a total mental health exclusion but at the full price, which didn't seem very fair to me.

I recently spoke to another broker who said not to bother at all applying for retail cover with my mental health history. She said I should I apply to increase my coverage and benefit period (to age 65) with my current super provider. However, my understanding is that they will go through underwriting again if I do that, and will potentially exclude me for the treatment I had since I took out the cover as that will then become pre-existing if we are changing the policy (I hadn't had any treatment for at least 10 years before taking out that default cover in 2013).

So without further waffling, my questions are -
1. Do I have any chance of getting insurance under a retail fund?
2. Can the insurer check my medicare claims history? If so, how far back?
3. Is there a better insurance product I could be getting by rolling over my super to a different fund? (broker said some super policies do not exclude pre-existing conditions).
4. Slightly unrelated, but should I even be using an industry Superfund given that I am now self employed?

Any help with any of the questions would me much appreciated, thank you.