E-3 or TN Visa for Working in the States

Hi

I'm new to the forum and am hoping to get some advice and also give any if I am able now that I have joined up

My hubby is a Canadian and moved here on a professional visa last year (Melbourne) from the US (California) where he was working under a TN visa (I lived there with a TD for a few months after we married).

We have had our fair share of hassles at the borders between the States and Canada (and also Australia and the US as I visited often to see him) primarily just because of the visa's (secondary interviews and such) so we made the decision to come to Australia to live a while (I'm Aussie).

Hypothetcially speaking, should we wish to return to work in the US (well, my hubby) would it be best to go under the TN visa again, or wait until he has Australia Citizenship (along with his Canadian one) and apply under the E-3? I have only recently become aware of the E-3 visa (I hope I have that correct) and thought it might be a smoother passage than the TN seems to provide.

Warm wishes and many thanks for reading my post

E-3 is no simpler to get than TN, so since he can get TN immediately, why wait for OZ citizenship.