Thoughts on This 351, FSL 3x5

Saturday

Squat - 351, FSL 3X5

Assistance - Abs - 50-100 reps, Chins - 50-100, DB Bench - 50-100

Sunday

Bench - 351, FSL 3X5 (main work SS with 50-100 rows and face pulls (total for both))

Assistance - DB Incline - 50-100 reps, Weighted Push-ups - 50-100 reps

Tuesday

Deadlift - 351, FSL 3X5

Assistance - Back raise - 50-100 reps, DB Incline - 50-100 reps, Chins - 50-100 reps

Thursday

Press - 351, FSL 3X5 (main work SS with 50-100 rows)
Assistance - One leg hack press - 50-100, Dips - 50-100 reps, Curls - 50-100 reps, Rope push downs 50-100 reps

Agile 8 for warm up, a long with box jumps on I assume all days? I work as a postman so walk for 6 hours 5x a week.

Is that enough lower body assistance work to gain strength, size and ultimately progress? I always do a fair bit of volume just because it seems to work. I know assistance is just assistance but the thought of going into a squat session and finishing off with db press and chins is very different!

Thanks.