I've been using MTG Studio for quite a while, but there are a few things about it that are just annoying. They're small, but they're usability features that are lacking.
1. When searching, the search should loop. That is, if I search "sliver queen" in the card pool, but it returns "Sliver Queen, Brood Mother", it should loop back to the beginning when I press Find Next and direct me to the card "Sliver Queen."
2. When searching with the quick searchbar, pressing enter a second time should function the same as the Find Next feature. If I search for "llanowar", but don't get the card I want, I should be able to press enter and it will go to the next card with llanowar in the title.
3. Not a big issue, but live searching would be pretty helpful. Whether it be like MWS where it directs you through the database as you type, or like iTunes for example, where the card pool is narrowed as you type more. A feature like that would be awesome.
4. Making the abilities filter searchable. There's such a vast number of abilities, and it can be hard to find the one you want. A search function would be nice.
Just a few little nit-picky things about the searching that would be nice to see implemented (1&2 especially).