I would revamp your game a bit differently
Achievements shouldn't be automatically given just for playing the game. But instead eventually spaced click about hot spots through the entire game. Both in the Good and Bad paths.
One of the bit upsetting things I found about RfJ was having to play the bad path in order to get all of the achievements.
Here I was trying to set Marc up with Jess for a few days only to come to end and shocking dark ending with Chloe!
That was a psychologically haunting for a few days. I never expected to see such a dark ending in any adult game. gasp An did spoil the mood of Good ending. Believe it or not was teary eyed over Marc and Chloe because of that scene.. lol
When I came back to the game in order to play the good path. It really spoiled the mood during the Good Path for I was haunted by outcome for both of the characters from the bad scene.
I think better then having to play both paths in order to get to the bonus. Achievement should be hidden hotspots through out the game. Through out both paths. Such as ash tray in bar or door in the city center scene or a band instrument in the club scene. Something the player should hunt for through out the entire game.
It would also make the player slow down and enjoy each beautiful scene and story. As they forced to inspect and hunt for the hidden object
Like in real life employment Bonus' are not given for zooming through your work. But instead because you put in the extra effort and rewarded.
Then once you get all the achievements and bonus.
You automatically unlock a lets say scene menu where you can pick segment of the game in free mode. So you can revisit your favorite scene. Nor should the Bonus scene be accessible by way of the freeplay mode.