I have never used morphe so I couldn’t tell you, but I like how grayjay let’s me make playlists and download offline across multiple platforms while still allowing sign in, plus, I know a lot of people won’t like this, but I do like the ability that it still allows to give me personalized results, which is something that I noticed the other YouTube front ends don’t do without workarounds. it also gives me those personalized results across all platforms.