It's funny you mention Harley as a not soft name as I think it's very soft!
My favourite "soft" name is Gabriel. So gentle and musical yet still strong, love it.
I would agree with Julian and Christian and Noah, but for me Rhys and Finn are very adventurous sounding--maybe it's because of the choppy one syllable.
Others that are a bit soft imo:
Here are some that are soft, but I still like. Excuse any repeats:
I also find pretty much any unisex name soft. Avery, Peyton, Skyler, Sawyer . . . all soft on a boy to me.