Hi fhansen - I think you’ve got it just fine
Certainly St. Teresa strongly believed in praying without ceasing . . . in fact, one of her strongest influences was Franscisco de Osuna who wrote a very popular book at the time on active recollection (Third Spiritual Alphabet). Much of what St. Teresa wrote was based on his book, it’s just that her focus and interest was more on the infused side of things. Everything she addressed in the 4th mansion and beyond in Interior Castle is a different slant on this . . . some of it falls into what is sometimes called “ordinary” contemplation while other parts are considered “extraordinary.”
This might crash and burn

but I thought I’d use the analogy of natural sleep to try and help explain what St. Teresa is saying in the 4th and 5th mansions . . . since there is a certain similarity, at least in my mind.
The Prayer of Recollection (4th mansion) is “like” dozing off when we fall asleep. The Prayer of Quiet (4th mansion) is “like” a light, fitful sleep . . . mental distractions being what prevents a deepening of the prayer. The Prayer of Union (5th mansion) is “like” a deep, sound sleep . . . the entire soul being captivated by God in a loving embrace.
I use this analogy because the Prayers of Recollection, Quiet and Union “flow” together much like natural sleep does . . . one is simply a “deepening” of the other. And all of this falls under the “ordinary” way of contemplation . . . open to all souls who yearn to be united with God in this way.
Ecstasies, raptures, flights of spirit, transports and so on (6th dwelling) are also types of infused prayer . . . but they are considered “extraordinary” graces. The main difference from these prayers and, say, the Prayer of Union, is that the extraordinary ways come upon the soul more suddenly and unexpectedly (often while in public), last longer, and are “felt” more exteriorly.
St. Teresa describes the physical effects of ecstasy/rapture as the body is left as though dead - unable to move, breathing slows, temperature cools - for the duration of this prayer. Flights of spirit/transport is the physical sensation that the soul has left the body or is “moving” at a rapid speed . . . paraphrasing St. Teresa, like a bullet leaving a gun.
Visions, locutions and revelations are also “extraordinary” graces. They can occur in any of the “states” of infused prayer discussed, ordinary or extraordinary.
All these extraordinary graces are actually spiritual imperfections for the simple reason they are felt so exteriorly (ecstasy etc) and rely on our senses to interpret meaning (visions etc). The Prayer of Union, in comparison, is entirely spiritual. It is interesting to note that St. Teresa stresses that when the soul is brought to the transforming union (perfection here on earth) these phenomena cease, however the “ordinary” infused prayer remains.
Hope this helps . . .
Dave