The list provides seeds, links and a short description of the starter island and it's surroundings. No special order. I just enjoy looking for Island spawns.
1: ys3gYb8k56
Small island in swimming distance to the closest boss.
2: 3wuuiCXwTC
Two medium sized islands isolated from the first boss.
3: JFezuBPp0G
Very isolated starter island. Medium size. Map has fairly large islands elsewhere.
4: UXL0hU9qKf
medium size started island. Pretty hard spawn regarding progress to bosses.
5: S8gqZJnHfK
Tiny starter island with swimming distance to closest land. Good north to south axis acorss the map nearby.
6: esrAdQkm5q
Medium sized starter island. Requires a fair bit of sailing to progress.
7: PfA9wj3f2v
Mediun size started island. Large islands nearby. First three bosses require little movement.
8: 0L4FgEDG4J
Tiny starter island with swimming distance to several medium islands. Not optimal for fast boss progression. Good for long exploration sessions.
9: i3CGcgqFv2
Small starter island. Possible to progress without sailing. Fairly hard progression to bosses.
10: 5rOsEmaRy5
Small starter island with the first three bosses not requiring any sailing.
11: EKmNbxiuhK
Medium sized starter island requiring sailing to reach the first boss. Possible to reach large portions of the map with little sailing.
12: AnGFH3FwQG
Mediun sized starter island only separeted by a river from the nearest land.
13: WtanWD7Eiw
Medium sized starter island with swimming distance to the first boss. Bad place if you want your permanent base close to the spawn.
14: I6SSa7afVu
Small starter island with hard progression to all bosses after the first one.
15: Z3xHPebym3
Medium sized starter island with possibilities for early iron.
15 island spawns for all island enjoyers. I've searched through 100s of seeds and saved some of the more interesting ones regarding islands.