Personally, I wish Topps had destroyed the "extra" sketches (as horrible as that sounds, I know). It just kind of throws things off and makes for confusion.
Also in retrospect, I would really prefer if Topps had done the comic sketch cards as part of buying the comics. Maybe "buy 4 and get a sketch card". Would be incentive to buy the comics and perhaps spread them around, while keeping the collecting in order and preventing people from getting less-than-desirable previous series sketch cards, etc.
This whole thing has made collecting the sketch cards a bit backwards, and I'm not a big collector or anything.
And it basically means the eBay dealers who can throw big $$$ at Topps are the ones who get the sketch cards, post them on eBay, etc. Of course Topps gets the $$$, which is their bottom line, but it's feeling more and more like that's the only important thing...