@ssjmaiko: NO, for sure after 30+ volume, ther's some progress.
!!Spoiler alert!!
Tech:
- they now have refrigerator (induction type, you put ice in upper section). Ikuto made it.
- Cotton candy machine, etc
Romance:
- a lot, a little bit in every girl, but after 50+ chapter you'll know every girl characteristics, background, story, etc.
- unfocused, but cover every aspect with balance (except some chapter which emphasize ikutoxsuzu and ikutoxmisaki at later on)
Mystery:
- the most developed aspect in this manga, every 20+ chapter you'll get 1 "unsolved" mystery of the island. You'll start to wonder: how large is this island to have another "wonder" in every section?
- some example: what is the dino that ikuto saw in underground? Where's & what is Suzu's mother? What about Tonkatsu? Where's his parents? The Kappa? The aliens? Why the animals can speak/understood by the islander? The dream world? Ikuto's Grandpa? etc.
- almost nothing is solved, but at every 20+ chapter it keep increasing. This truly is an island of wonder.