So, the ending of KQ3 obviously makes me think of KQ4 (which starts, like, seconds later). I was quite fond of it. And thus I wonder - was this the first video game I played with a female character as the protagonist?
Obviously, she's not the first actual female character leading a videogame. Ms Pac-Man is technically female (although I'd argue not a character) and there's Metroid, of course. But I never played Metroid.
The Princess is a playable character in the english Super Mario 2 and might sortof count. She's only one of four, but I played her in every level unless there was some secret reason not to. Not just because of girliness, I also liked her hover power. However, datewise, that launched shortly after KQIV, and I can't tell what I might have played first. (I probably played KQIV right away, as I had the AGI version. I had both versions eventually, but I had tons of fun messing with the debug codes in AGI.)
I was probably a happy kid that year though! Two major game franchises that I was big fans of, now letting me play as a girl, and the girl wasn't useless. Crucially, owing to the limited graphics and sound of the time, there was not a whole lot of extra characterisation heaped on either princess. They were both blondes in skirts, sure, but they weren't stuck being comically kawaii with high-pitched squealing. In fact, the Rosella of my mind was pretty fierce.
I mean, imagine the day that girl's had! (series spoilers) Her kingdom is in ruins and she's either volunteered or been dragged off to DIE at the hands of a dragon. She gets rescued at the last minute by a total stranger who turns out to be a long-lost relative and stumbles home, at which point her father promptly keels over from a heart attack. In a panic she flees to a magic mirror and gets yanked through it to another place where she's manhandled by flying monkeys, swallowed by a whale, menaced by man-eating ogres, chased by zombies and mummies, swims to and from multiple islands, gets locked up, threatened with a forced marriage, and has to save multiple people from death... and this all takes place within 24 hours!
Rosella of Daventry by ~Flameprincess88 on deviantART
This girl. She rocked.
I don't recall there being any suggestion at all that there was anything odd about a girl going adventuring, or that she was in any way inferior to the previous lead characters. In fact the ending of Kq3 showed that she had an adventurous spirit, as she was right there reaching for the hat along with her brother.
And even though, later, I did want her to get together with Edgar, I was pleased at the time that she didn't instantly marry a guy just because he was present and suddenly not-ugly. (However, I was not hugely fond of KQ7. It was a letdown after KQ6 which I thought was great...)