I like the last idea settlerjoe, to provide more information in the total value field. What would you think would be useful?
Total value as it is now, and total value of cards worth > 30 cents, perhaps? Or 50 cents?
Something like that, yes. Perhaps allow the user to input the cutoff amount? Also - would be great if all basic lands (except special ones like foils, full-art, etc.) were excluded, regardless of the price cutoff. I've seen way too many times a basic land worth a penny at most is listed for as much as 50 cents on deckbox.
However, if you're going to fix that cutoff at a certain number, I wouldn't go higher than 24 cents, as anything worth 25 cents or more has real trade value, especially for Pauper players. Perhaps you could seek input from the Deckbox community for what that fixed cutoff should be, but I imagine it will be different depending on the type of player. Pauper players such as myself would rather have a lower cutoff of around 20 cents, I would imagine.
To elaborate:
With in-person trades at my LGS, 25 cents is about when people start to pay attention to the value of the card in a trade ("we're at $22 for you, $23 for me, how about throw in 4 of these 25 cent cards to even out the trade"). On the other hand, it seems like cards valued at less than 20 cents are thrown in for free in some of my trades.
There are many important cards for the Pauper format that cost less than 25 cents according to Deckbox (but which often differ by a few cents from TCG). Ghostly Flicker is .21. Atog .25. Gorilla Shaman .20, Kor Skyfisher .19, etc.
If you want to get a sense for Pauper card values, you can look at this deckbox list I made, which represents the contents of a 53 deck "Pauper Battle Box" (decks that have done well in at least one online tournament in 2014-2105) that was publicly posted to the reddit/pauper board:
http://deckbox.org/sets/1280397
I'm gradually trying to acquire all of these cards, in the listed quantities, mostly by sifting through the penny card bins at my LGS. These cards have real value to paper Pauper players, especially the ones with 5 or more listed for the quantity (it means the cards are used in multiple decks).