This is a tough question!
I played my first VN years back, and it was so unmemorable that I can't even remember what I played.
Hence, I'll just mention the first VN from my memory.
Da Capo II was probably my real first galge experience, and I loved all the girls. I disliked the H scenes though; they left a bad aftertaste in some of the routes. ;_;
Starry Sky in Spring on the other hand, was my first otome game, and like DCII, I adored all the characters.