Sky Islands/Cloud Dimension, Flying Pigs, "Larger Phantom" Boss Battle

A Sky Dimension. Where the phantoms "come from", possibly even other flying mobs could be there too. Bats, Bees, Parrots, Fireflies*(I know, but firefly bushes could adda nice touch to the beauty of the landscape.), Vexes could spawn here at night. Happy Ghasts and Ghastlings could spawn here. Phantoms of course. But my thoughts on the Sky Dimensions appearance are cloudlike island structures that connect (for the most part), very similar to the end islands. Could easily refer to them as Sky Islands. Either way, these islands could be full of grass, flowers, trees, and flying wildlife. My thoughts with the phantoms are that they would spawn during day and night in the sky dimension but be passive during the day. Perhaps somewhere in the Sky Dimension is like, a larger phantom boss battle? Giving off vibes of the Elder Guardian fight, there could be multiple of these "larger phantoms" anyone could pen a creative name for it. I don't have one in mind. I also think a fun passive mob you could put into the sky dimension would be flying pigs. Pigs with wings up in the sky islands dimension, just feels very "Minecraft". The way to access this "Sky Islands Dimension" would be to build a portal, but perhaps you use a feather or a new item crafted with feathers to open the portal. I'm not sure what blocks would be good for a portal for this dimension. You could make it Glowstone; like the original Aether mod as a nice reference; then the Nether would usually come first in playthroughs