I just whip the domes off once they are good and rooted. There's no need to slowly acclimate them. Just, if a species seems particularly delicate, I let it hang out in its dome longer and give it time to develop a bigger root system.

They will be fine in an east window. I'm not sure what you are using as your "dome." If it has holes or gaps so air can move in and out, then you can take the domes off either before or after - whenever you feel they are stable. But if it's a completely closed system, like a plant inside a sealed ziplock bag, it can roast in direct sunlight, which is pretty tragic. It's the same logic as with cars in summer - keep the window cracked open.