The lower the actuation vacuum the harder the throttle has to be pressed to cause the extra advance to be taken out by the canister. It acts a bit backwards from what would sound normal because you're going from high vacuum at light throttle to low vacuum at heavy throttle. A high number for the vacuum advance to be all in at means that it will take less throttle opening to get to that point. That means that you'll have less timing at a given load and less pinging as a result. Limiting the timing means that you're starting at a lower total timing amount as well.

Adjust the vacuum canister with the small Allen wrench until you just get a small amount of pinging as you quickly press the throttle, then go back until that is gone. Then change the amount of timing that you have with the limiter, adjust the canister again and so on until you have your throttle response (and fuel mileage) back to where you think it should be. This can be done over the space of a couple of weeks and is checked in normal driving, no need for special conditions. This will be good practice for tuning your EFI system!