when you are experiencing negative g, who has control? As you are learning in gliders, practicing interesting maneuovers is best done at altitude....both spins and negative g. I think negative g is enormous fun, first you do a bit of a dive, then pull up and keeping flying speed, push over, and enjoy rising up in your seat (of course the straps are snug enough so you don't wack the canopy with your head.)
And all the dust and grass clippings rise up around you. If YOU HAVE CONTROL, it's fun. If the instructor is demonstrating, it's more like torture.
Likewise, with the spin and recovery, I think half a turn is plenty, to diagnose the spin and recover, in a K13, whereas some instructors think that a couple of turns is required, they put it in a full spin and hand it to you and say now recover! that teaches nothing at all, to feel a spin you should put it in the spin yourself.
Worth taking an aerotow on a good soaring day, climb to 3 or 4 thousand feet and just mess around in a K13. The more you do yourself the better you will enjoy being in control. Have fun! don't worry about solo. That comes when it comes.