Your playing is coming along. I like the songs you pick too. You've got the tone and the control sussed. You're pitching well too. I think you should work on phrasing and varying the dynamics. Perhaps a little bending to give it more expression. Perhaps a litlle vibrato on the long notes. You sound to me like you're holding back.
When I heasr an instrumental version of a standard I can hear the key phrases , especially the title and it's these you need to almost sing through the sax on the head.
When working up a new song on the alto, I like to listen to Ella Fitzgerald to hear how it goes. She always seems so precise with the phrasing and pitch. Then a version by Sarah Vaughan for a looser feel and a little more soul. When I think I've got it, a version by Nina Simone let's you know how far you have to go.
Keep up the good work.