My GPP based on DVD please critique

PBs:
400m: 51.12out/52.17in FAT
200m: 24.07 FAT
185lb, 6’1 athlete
Squat: 315lbx1
Clean: 100kgx1
Bench: 185lbx3
VJ: 29"
Training age sprints: 3yrs, 2yrs mid-distance prior
Summer focus is speed development

GPP SCHEDULE:
Phase 1
MWF AM: med ball circuit 1000-1500 tosses
MWF PM: hills (as on graphs) + upper circuit weights
TThS AM: tempo big circuit + sit-up circuit
TThS PM: explosive med. ball (as on graphs) + lower circuit weights

Phase 2:
MWF: hills or track (as on graphs) + plyos (track days) + hurdle mobility (track days) + lower circuit weights + med ball circuit 1000-1500 tosses
TTh: expl. med. ball + tempo big circuit + upper circuit weights + sit-up circuit

Phase 3:
MWF: track (as on graphs) + plyos + hurdle mobility + upper & lower circuit weights + med ball circuit 1000-1500 tosses
TTh: expl. med. ball + tempo big circuit + sit-up circuit

No plyos in phase 1 b/c lack of access to track & HJ pits/high boxes is there a possible replacement? e.g. VJs
Phases 2&3 have no AM/PM split b/c of job
Hurdle mobility only when on the track for workout, tempo is done on grass fields

Questions: based on my maxes should i be doing circuit or stage weights?

how can the GPP be lengthened for an athlete with medium-low performance rather than medium-high (as per the DVD and running workouts)

Comments welcome, thanks!

Explosive med-ball is high-intensity work. While there are times when high-intensity work can be done everyday…the closer you get to the SPP the more the high-intensity work needs to be gathered together so that sufficient recovery time is given. So, while it is ok for you to be doing explosive med-ball work on tempo days during the first part of the GPP, it needs to be put together with the other high-intensity components as you move towards the SPP.