To echo the sentiment of the rest, patience will be the key here more than likely. We got a '17 hatchling this Spring who'd barely been handled and she was extremely flighty and nervous to begin with. She'd tense up as tight as she could when we'd hold her and struck out on a few occasions when we would clean her tub. Fast forward to now and she is much more comfortable with us and being held. She still gets a little nervous when you first are opening up her enclosure, but once she is out and realizes what's going on she relaxes and will hang out with you.

From what you said, it sounds like you've got all the right ideas, so just keep at it and I'm sure you'll start to build that trust over time.