Yeah, it's tricky because basically all solar arrays (rooftop and utility) all come online at more-or-less the same time so there's a huge influx of supply which drives the price down.
You can get a sense of it if you look at the daily breakdown:
https://explore.openelectricity.org.au/energy/nem/?range=1d&...
You can see the demand peaks around 12pm and 6pm.
The price goes negative around 2pm most days, in which case, as a solar only operator you're losing money to generate power, so quite often there's curtailment.
And then at 6pm, the sun is down so solar-only operators can't capitalise on the opportunity.
So unfortunately it's just a very limited opportunity to make a profit on your investment each day. More demand during the peak generation time would help!