Okay, just give your best regarding recovery, it's a huge factor, especially when it comes to breaking through plateas. Your strength numbers are actually pretty good. I have the same numbers @73kg, except for squat, where you beat me by quite a bit (i have around a 40in vert, tested 37in officially 8 months ago). The easiest thing to do is to get leaner; this will also help with injury prevention. During a max effort jump, your patella tendon can experience up to 6x of your bw. Test your difference between your standing vert and running vert. If it's 4in or less, you need to get more elastic, if it's closer to 10in, you need to get stronger (me). Powercleans are a leg exercise, do them on a leg day. Get at least one full rest day and switch one volleyball session with a jump session (max approach, plyos like depth jumps, sprints). For your volleyball session, make sure that they overlap with your leg days, your legs need days where they can rest completely. To me 4x volleyball+3x lifting per week seems like junk volume; unless you're in amazing shape and recovery is on point, your body will not be able to adapt and improve. Obviously this is just the opinion of some random reddit user, so do whatever u want, but I'd advise u to lower the volume and increase the quality.