Some rear DR's are less expensive new than the wolf tooth extender some buy to try and make the old DR work.
Hangar extenders only allow you to get clearance from the cassette. Not increase the capacity so you can have huge differences from the small/small to the big/big combos.
What you need to look for is how close does that jockey wheel get to any of the cogs as you go from the smalls to the bigs. In the other direction, you don't want any slack in the chain as you go to the smalls.