I honestly don’t think it matters what topic you start with or in which order you do them. Quant will supplement portfolio mgt when discussing capital market line/CAPM/SML which are related to regression analysis, which is what Quant covers. But in general, I don’t think any one topic precludes you from learning and understanding another. As a side note: I think Quant, albeit one of the less heavily weighted topics, is actually one of the hardest.
I get confused when people argue for doing FSA or Equity first - as though it’s foolish not to. Sure they’re more important and I guess that strategy can’t hurt, but doing them first changes nothing in my mind. Perhaps its bc people assume you are fresher and more committed bc it’s still early in the game, but if anything, I’d probably suggest making them some of the last topics that way they are fresher when you do your review. That assumes of course you allot yourself an equivalent amount of time to study them.
In the end, I don’t think it matters. Sure, the topics are all connected in a way, but none of them stop you from learning anything downstream.