I have played both HTA and LSH and love both, so I would like to suggest an idea from HTA for LSP. Image Gallery and Achievements
Image Gallery
I know that LSP already has the flash drive that gives you the gallery but this gallery will be about the art (not the animation) of the ghost you captured or even the secret animation/NPC, The unlock system is like HTA and Animation (Have to see the animation once). I'd like to see the ghosts in the game have their picture like the HTA Gallery Picture. (Although, this might make more amount of work for the game)
Achievements
This system is like HTA Achievement, This will make the game have more things and more goals to do (more or less), The quest could be capturing the amount of ghost type, getting money to X amount, or finishing the mini-quest of the game.