Personally I don't like having to train someone to be a nurse while dealing with critical situations. Much better to have an experienced RN and build on established knowledge. That's just my opinion, but to think of experience -- especially stepdown -- as a detriment is stupid. But this placement is for school, correct? So when you are applying for positions, you will be starting as a new grad -- technically not with stepdown experience. I would think that your preceptorship *might* give you an edge compared to the next new grad, though. ICUs weren't even an option for our final practicum when I was in school (early 2000s.)
A good chunk of my unit was hired from our stepdown unit. My manager has also hired people from psych, L&D, med-surg, even one from LTC. She hires a very occasional new grad...I want to say 4-5 yrs ago she hired a new grad.
They like to see confidence but not arrogance (that type is very very dangerous, esp in a new nurse), excellent critical thinking skills, and a strong pt/family focus. That's been my experience, anyway.
Enjoy this experience, soak up all the knowledge you can, let your heart for patients and trauma care shine, and I'm sure you will reach your goals.