OK so I played the game, but I didn't beat it. I got up to the area with the thunder enemies and I just got tired of playing.
I got tired of navigating the mazes and fighting the repetitive combat encounters, so I felt I had seen everything I needed to see and I just quit. There wasn't a lot of strategy involved so I just kept spamming the attack button over and over used an occasional special attack without thinking. The story wasn't interesting, it just didn't feel like it was developing enough. There's some attempt at humor, but it just wasn't enough of it to warrant a full playthrough.
It looks like there was an attempt at original artwork, but the sprite work for the enemies feels rushed. They just don't feel like they belong.
RPG Maker can be used to make a great game if done right. I don't know a whole lot about how RPG maker works, or to what extent you can modify it but here's a couple suggestions.
Don't make mazes. They are just not fun. I didn't like them in Phantasy Star II and I especially don't like them now, especially with all the backtracking. Maybe you should use keys to open doors or switches to open hidden walls, anything to keep the game engaging. Maybe boobytraps? Anything besides choosing a random direction on what to follow is good enough.
The music and audio sound effects are actually pretty decent, and the theme fits.