1. I cut them thinner.
2. I made sure they were all flat on the pan (the best I could using one pan, may have been wiser to use two).
3. I made sure they were all coated with olive oil, salt and pepper before putting them in a hot 400F degree oven.
4. I turned them in the middle of baking, after about 15 minutes.
5. I let them cool a bit before eating them. Patience - something I'm trying to get better at.
I baked them for a total of about 25 minutes. The fingerlings did much better than the sweet potatoes, but the thinner cut ones definitely were more firm and crispy.
They weren't perfect, but they were better than I've ever made them! And they tasted good, which is all that really matters.