That doesn't really sound like a problem with "Getting outbreak back" though? Rather a problem with the spawns associated with the outbreak state? That's an important distinction, because the problem with Famine "disappearing" is an entirely different one. It doesn't sound like your problem would be fixed with "more outbreak".
It's a matter of point of view: if you're primarily interested in the technicalities of the BGS, then Famine was gone and Outbreak wasn't. If you're primarily interested in collecting Engineering materials, as I am, then both Famine and Outbreak were removed from the game as viable G5 mat farms by 3.3.
And since this thread was started by a post from Factabulous pointing out that it was now possible to once more farm Famine states for Datamined Wake Exceptions, I thought it reasonable and relevant to hope that the introduction of a new pathogen would mean that it would once more be possible to reliably farm PIs in Outbreak systems - which is what "getting Outbreak back" would mean to me.
On your point about spawns - before 3.3 HGE spawn rate was held to be linked to system population size. And you could find large-population Outbreak systems. Since 3.3, my impression is that:
a) the rule about large-population systems being better for HGEs seems to be holding;
b) Outbreaks have tended not to occur in large-population systems.
If a) is indeed true - I admit I have no hard data but if HGEs of a given type are available at all I'm finding them in large-population systems - then a contagion that spread the Outbreak state to many large-population systems would indeed see my problem fixed.