I'm not having a go at Choice Bro...but 15000' at 55 track miles to run (for those who don't know CHC, it's about - for ease of figures - 10 nm to land from OD to CHC) seems reasonable in all the jet types I've flown.
If the grey matter between the ears were consulted a little more often than simply blind obedience to the 'funny little green box', then the whole shooting match might work a bit better.
Try amending the descent speed from it's cost index default to cruise MN into 300 KIAS - I bet it'd work every time (ignoring massive tailwind). A different kind of energy management!
Used to use 21000' at 60 to run in some types, 18000' at 60 to run in the others. Either way, the CHC STAR constraint should be easy to meet without slowing up.