You need to find the balance between, disciplined practise to progress and enjoying it so that you don't feel like it's a chore etc.
After all, everyone who plays a musical instrument is doing it for their enjoyment.
If you have 1 hour for playing your saxophone in a day then I think 30mins of that should be practise, and the other half should be enjoying by doing whatever you want.
The important thing with a practise routine is to keep it varied, otherwise you get stuck in ruts.
since you're only practising for 30 mins, focus on your weaker points your teacher/yourself has picked up from your general playing.
So maybe you need to do some long tones for a few days, and then you notice your vibrato isn't quite as good as you want it for a certain piece, so you start practising that etc.
I would work out a 30minute session that focuses on one aspect of your playing and touches slightly on other areas. Then chose one of these appropriate to what you are playing generally and want to achieve in the short term.
for example, you are having difficulty with a fast bit of music. You may realise that the problems are
1. finger and tongue co-ordination
2. not being able to get the fingers to play the notes
3. reading the rhythms
I would then say, find a bit of music to sight read, for 10 minutes.
If the piece is in C major, play C major, A minor, G major, E minor, F major, D minor scales. As these are the most likely to be used in the piece. And play these scales slowly to a metronome gradually increasing speed for 20 minutes.