the problem: i use my show needed page to see whether i should move a deck from keeping to collecting, so it would be easier to see a number of cards i have from the deck
the solution: display amount of cards you have in each deck in a category
caveats: you already have the show_needed mod (not the show needed as text mod)
in the show_needed mod find this toward the end
echo $check.': '.$diff.'<br/>';
swap to
echo ($all-$need).' - '.$check.': '.$diff.'<br/>';
for an output like

could also swap to
echo ($all-$need).'/'.$all.' - '.$check.': '.$diff.'<br/>';
for an output like

for an explanation for playing around with it: