Here's another idea spitballing here based off those Equestria Girls choose your ending. Something happens and you have three choices to make resulting in a different end result for the plots focus character and such. What if Spike who just started high school as a Freshman ended up meeting the Rainbooms, and each one of them offers to give him a tour. You can pick between the seven Rainbooms, Twilight, Rarity, Rainbow Dash, Sunset Shimmer, Pinkie Pie, Applejack, and Fluttershy. Which each different pick they'd show him various places in the school while getting to know each other, and in the end the two develop a friendship with hints that could lead to romance.

Sounds like an interesting idea. Reminds me of those Japanese light novel games.

Another interesting idea would be that in addition to the established romance, is that each girl in the mane 7 helps Spike to have friends his own age, for example if Rainbow Dash is chosen, she could introduce him to Scootaloo, Rumble, Pickle Barrel and / or Barely Barrel or if Sunset is chosen, she could introduce him to Button Mash (because of the gaming) or even Snips, Snails, Diamond Tiara and Silver Spoon (just because they were villains xD)