your arrangements have a lot of little fast fills and licks hiding in them that always feel great, they sound natural and spontaneous but also do a lot of subtle things that my brain really likes. in a lot of your videos you'll highlight one and sort of break it down by showing the notation or your hand on the keyboard, which makes me wonder: do you come up with those lines just by playing them, and then analyze the details afterward? or do you compose them in advance so that they sound spontaneous, but they're actually carefully controlled?
the big prominent ones are probably written into the song, but the smaller ones are probably found during production. regardless, nowadays i don't use staff notation either way. the big solo in "airport terminal" is improvised. the big solo in "la de da" is mostly improvised except it was written into the song that i would specifically quote "where did all the good times go". a prominent riff such as the one after "celebrate" in "meet me in september", was written with the songwriting, and same for the one at the end. although notation wasn't used. but transcribing notation and chords is trivial for me because i am fluent/literate in notation and chord symbols, so for me that's no harder than writing down a sentence that i heard someone speak