I have around 20,000 friend points and only 6 or 7 good a, Heracles, Camilla, Emiya, Siegfried, irisviel, Medea and Medusa, I don't know if there is other use to the friend points, so I don't know if is worth saving them.
If you dont have a hans, roll until you get at least 2. np5 hans is a very potent support and easy to get. People only save FP once they have almost all the 3*s, so that when new 3*s come out(Ex: Hassan of Serenity), they can roll for them without SQ
I mean, aside from servants you may not have that are useful, like hans or hassan or whoever, I like to save up my friend points for events. The FPs can get the 3* event CE, granted its very low, but yeah. You can grab extra hans or whoever on your free friend roll each day, but the friend points can get you a free event CE which will help with drops. Thats my recommendation.
