I have 2 cockatiels--one male, one female (NOT a breeding pair I might add), and my female thrives on not having her wings clipped. She's never flown into walls or windows and we make sure to re-cage her if the door leading to outside must be opened for whatever reason, regardless how briefly.
My male cockatiel came to me as a rescue from an abusive, neglectful situation similar to the one seductivereptile described her bird as being in prior to the change of scenery. He had a 6-inch tall pile of poop in the cage, one swinging perch, a dish full of hulls, and water so nasty I had to throw the entire container away. His wings were so weak he couldn't even sit on my finger properly without falling off, so I wasn't worried with clipping his wings. Instead I worked to exercise those wings, by letting him perch on my finger while I gently held one of his feet with my thumb, and then lower him to the floor while he flap-flapped away. We would repeat that a few times, let him rest a minute or so, then do it a few more times before returning him to his cage. For the first couple of months, though, his impulse was to bite, so we would use garden gloves to get him out of his cage. Once out, he was fine and the gloves could come off, and he'd stair-step on our fingers like he'd been doing it all along.
Once his wing muscles were strong enough to support flight, I allowed him a closely-monitored trip around the room, with someone standing in front of all the windows that might appear tempting. He could only fly in a straight line, stopping until he got to something or someone he could perch on (usually in some very clumsy landings) and would then proceed to chirp & holler until he was escorted back to his cage. We monitored his flight for about a month and decided it would be better to keep him clipped.
Seductive, with patience and lots of TLC, your feathered friend should come around. My male went through a difficult molt after I got him, and he'd never been exposed to a bath either. I've had him about 8 months now, and he still protests somewhat when I bring out the spray bottle, but not near as much as he did with his first bath. Do you fill your spray bottle with hot water? I fill mine with hot water from the tap, and by the time the water reaches their feathers, it's about room temperature, which is just fine for cockatiels.
I should also mention that he had some stubborn feathers underneath his wings that didn't want to shed their sheath...they'd been there for several small molts. But a few weeks ago he allowed me to stroke him underneath his wing (no glove), and he just sat there calm as could be, wing slightly raised and his beak half-open like he was smiling! Have patience, and work in small steps. =)