You can. You just can't order the display within the collection. Go your cards page. Click on the green letters, Create a collection . . . , name your collection, then select the cards you want to be included in this collection, save (you have to save each page of selected cards before you move on to the next), et voila, you've corralled a portion of your deck into a collection. Here's my The Arctic collection as an example:
Also, don't just junk the cards you don't want anymore. Some, like your epic version, can bring you big bank on the card market if your timing is right.
Polls are already preserved here but if there is sufficient interest I could put them into a dispatch with more readily observable results.