I've been looking at some of these and other ones I've come across in person and to me it looks like a jungle island that is decently far from its parent biome but is also Jungle M or edge works nicely as well even if it is only ~300 squared. Lemme know if you come across anything like that and I'd be glad to look at it. ALSO pretty important to mention I don't mind if it is up to 10,000 blocks out. Travel is trivial thanks to the nether!
The first one I remember seeing before cause it's surrounded by icebergs lmao
The size of the second is great, it just doesn't feel too much like an island
third ones nice as well, icebergs kinda give it a weird feeling though.