Completing NL Collections

I’m sitting at 220k stubs and am looking for some advice on completing the NL collections. I’m not interested in completing the AL right now, but I really want the Sheffield. I’ve still got a decent amount of teams to finish, but really I just need to get a few of the expensive cards before I can run through and fill out the rest of the teams. I’ve got the Dodgers done, so really the only expensive cards left are Arenado, Yelich, DeGrom, and Scherzer. Does anyone have tips on how to complete these collections without just running through stubs on the market?

Sell off everything that isn't nailed down?

Without sitting on the market all day long flipping cards, the best way to make stubs is probably BR, but you need to be good enough to go 9-2 relatively frequently.

Easier way is Showdown -

1. Each mission (most are quite easy) gives 200-500 stubs.
2. The mode provides a lot of XP for the time you'll invest - which powers you through the XP path...which provides salable rewards/XP bonuses.
3. The exchanging the TA vouchers also works you through the TA paths, which provide stubs and TA packs.

That coupled with selling everything ever get that isn't LS or No Sell...I seem to make a lot of stubs each time I do Showdown. And a run only takes about an hour.