They only last for a few weeks so yes you have to keep up with it all season long and make notes about who it was about and what the story was. There are good and bad storylines that for sure affect their draft stock. Not by a ton though.
As for waiting tell next year to use the tool no don't worry about that. While the storylines play a part it isn't that huge. Using the tool outweighs not using it by a huge amount.