1.5 isn't long enough for a lesson slot, no wonder you feel rushed and it's no good for anyone when things run late. 0.8 is plenty of aeroplane time to get the lesson done in the early stages when the student is well prepared. The things you learn on the ground are just as important as the things in the air so that's not "wasted" time especially if you are at an uncontrolled aerodrome and not stuck at the holding point. Plus the instructor is entitled to be paid for that time. Sometimes lessons can overlap and a good instructor will be able to improvise according to the conditions if necessary. If they are doing it because they are rushing to get back for the next person or last light then that IS a problem you need to address with them. In a smaller aeroplane there is the issue that it will take a while to get to altitude for the stall recoveries so that should be taken into consideration when they time the lesson slot.
When we get students come in unhappy with their flying schools we always encourage them to talk to their instructor first and often these things can be resolved without all the upheaval of moving schools.