i should pull for this gacha?

I's just that i always get a 4☆ Kasumi instead of what i want: I pulled for Wedding Rinko and i got first cool type ☆4 Kasumi, after i pulled for Wedding Eve and i got Wedding Kasumi, i pulled for raining Eve and Saaya, i didn't get both but a ☆4 Kasumi, well and then i pulled only for the ☆3 Railgun collab Saaya and I DIN'T GET HER and correct you guessed right, i get the collab ☆4 Kasumi.

So i'm scared of getting another ☆4 Kasumi instead of Rui and Tsukushi :(