I like the idea of the drifting islands!! They are also beautiful to look at. The main idea is great - namely: islands, drifting, getting bigger, looting, building - love all that. :-)
I just do not like hectic, stressy games so much... which is just _my_ problem, not yours or your game's ;-) ... I would love it if it were more slowly, building-focused and not so much running around like a weasel on coke. For instance, building some tower-defense like structures on the edge and then move to some other island etc. BUT, yeah, that would be a totally different game then ;-)
Also, I had problems "steering" the island controllably. When the other islands are far away I cannot pull them, and when they get nearer, they are too near - you have to run around to do stuff instead, then.
Last minor CON: The music is not for me, it's quite stressful. It fits the hectic game in that regard, though.
Anyway, cool idea, well made, quite well polished as far as I see it. Keep it up. Really cool stuff!