As far as long tones go- I've always found that- if I'm playing in an acoustically interesting environment- actually listening to the tone of the sax is quite enjoyable. Try long tones into a bay window or in a glass conservatory.... it can get quite hypnotic after a while.
Practice (almost) daily in my waiting room at work which has a bay window, and occasionally in the conservatory at home which is extremely interesting acoustically depending on the direction of sound in relation to the angles ot the glass panels.