My thoughts would be much like yours. Keep everything else plain (or perhaps a subtle stripe) and perhaps pick out one colour of the tie as a solid plain square just to anchor it in the ensemble a bit.
I quite like Lewin's knitwear for simple jumpers etc. I guess Myer probably have them at inflated prices but I bought a navy merino v-neck online at the Oz site for $64 delivered the other day (still waiting on it). I have one of their lambswool half-zips and that's quite nice for the price.
Well I could wear whatever I want when not dealing with clients' management, it's my company. But I decided to start wearing suit and tie again most of the time when in town for several reasons. The main one was probably that it helps me get my head in to business mode and provide some futile semblance of work/leisure separation :-) Plus I've found some pleasure in trying to dress with some style.
And, as usual, the utter cluelessness displayed in the comments makes me despair for the future of the country. I must stop reading them. I wonder how people so apparently ignorant of almost everything somehow have complete confidence in their opinions.