Quite a sizeable update today, that addresses various performance problems with the various input widgets (adding cards one by one to collection, editing card details inline via the details panel, adding both to decks and inventory etc). Everything should be cleaner and snappier now, for the very bad cases it should be up to 10 times faster (e.g. editing the details of a Plains card when you have 100 separate printings in your collection).
There's more work to be done, but this is a first step in the right direction.
Secondly, you can now set Foil/Signed etc as defaults when adding things to Inventories / Wishlists. Also available for Mass Input (adding 1 of each card of an edition for example), in the editions pages for premium accounts.
There are many cleanups and changes behind the scenes here that might be causing some new bugs in the UI, so please let me know if you see any issues - pages not properly updating, dialogs not showing correct things while importing cards / editing details, etc etc.