Think the first idea will work better. One effective way to gain strength is to always increase weight.
Like:
Week 1
Set1, 150x5
Set2, 150x5
Set3, 152,5x5
Week2
Set1, 150x5
Set2, 152,5x5
Set3, 152,5x5
Week3
Set1, 152,5x5
Set2, 152,5x5
Set3, 155x5
Week4
Set1, 152,5x5
Set2, 155x5
Set3, 155x5...