Yep you have to know your league, then put your money where you get the most bang for the buck.
As originally stated, if you want the Big Fish IFA, you have to go all in on it. To the point of skimping on coaching and scouting ie taking whatever happens in the draft. The upside is you can potentially lock in whenever a generational IFA comes along. You probably never buy a free agent because you see them as overpays anyway. And if sometimes a season comes along when no great IFA shows up, or you eat a bag of money with nothing to spend it on, you take the loss and move on.
On the other hand if you completely ignore IFAs, you have a ton of money to spend on even mediocre FAs. If your league is light on owners going this route, you can corner the market - I've been in a league where a new owner came in and immediately saw no one was dealing so he bought up all the Type As and won the WS first season. You can have a competitive - if overpaid - team all the time and keep winning with veteran team depth, the downside is you probably never have the bright shiny toy player racking up awards.