I would hang them all at the same height with the rod just skimming the top of the window, creating a waterline around the room...ignore the ceiling height.

The height of a shower rod relative to the position of a tub is largely a matter of use and desired effect. Some shower curtains extend almost entirely to the floor while others drop just below the rim of an attractive claw foot tub. What is certain is the shower curtain liner needs to hang down into the tub below its rim so water does not splash onto the floor. Hanging a Shower Rod Shower curtains are commonly 6 feet in length from top to bottom. They are made longer as well. For custom bathtub designs, their length can vary greatly. If you are installing the shower rod anew and need to know where to hang it, the first thing to do is measure the length of the liner. If it is 6 feet long, figure that it should hang below the rim of the tub at least 5 inches. That means the rod should be placed 5 feet 7 inches from the top of the tub. However, consider the difference between the rod placement and where the liner attaches to the curtain rings. If the liner dangles 2 inches below the rod, you can add that to the height of the rod, placing it 5 feet 9 inches above the tub. The curtain also requires some consideration. It should not drag along the floor; rather, it should be at least 2 inches above it when hanging. If you want to showcase a claw foot tub, hang the curtain just a few inches below the rim of the tub. Here is a link that might be useful: shower rods

I think that the best bet is to make them as consistent as possible in relation to window, regardless of ceiling height.

It is 8 French Doors that actually one open on each end. I was going to use the drapes on each end and shears all in middle. You can move the drapes very easily and I pull them back from windows every day. No problem. So, I thought that I could do the same where the door we use often (on side of house and have electronic gate. So, only my husband I only one's that use it. I found a picture (wish I knew how to show it) Where it's exactly what I was thinking about. It would be drape on each end where doors open, but we rarely use but one door and I could pull it back each day or even leave it pulled away from door we use.Looks fine that way.. I don't even use it that much since garage connects to back of house off kitchen. I do think they would look much better hanging same length. The one wall we did ended up costing 650, but I told him drapes and rods are "an investment." You plan on using them for long, long time!