Consider a game with young witch, ruins, colonies, and two events. It's certainly possible to fit all those on the first page, but it also means that when none of those are in the game it might look a little weird. Spoils, Prizes, Travelers, Mercenary, Madman, and the Black Market deck don't need to be on the first page for me at all. I didn't choose putting everything on the first page as one of my 3 because colonies are already on the first page, so really most games won't have anything important on the second page. Doesn't mean that it isn't something that should be done are shouldn't be too hard to do, but it really isn't at the top of my list. I chose Automatch, VP counter, and Adventures.
VP counter should be extremely easy to do; you already have something programmed that calculates points at the end of the game, now just display it during the game! But on second thought I would replace this with API for sure in my three choices. Blankman is right, if you let people salvage your product for you we won't be nearly as mad at you because we can fix it ourselves. If there was no Salvager right now, I'm not sure what would have happened to this community...
It sounds like Automatch already will be available, great! Does this mean I can replace this option with a log on the side? That's pretty important too.
Adventures seems like an awesome expansion that will add a lot of depth to one of the deepest games I know. It means more money for you and more fun for us! You will have to implement it eventually, and sooner is better than later. Some of the mechanics in adventures require rewriting a lot of code because you made assumptions about how the game works. It turns out that you can play your estates. Also you can play that one card on your opponent's turn. Also there is exchanging, which doesn't count as gaining. And there are cards that have on-buy effects that you don't move or gain or anything (events, you could call them). In making your frame for the game, you want to keep adventures in mind so that you don't have to do as much work later.