Whoop, I should also have asked how many players. There is nothing wrong with your plan, but here are some alternatives.
1 Table (10 players)
Blue T25x20=500.00 (you will be one short of blue chips)
White T100x55=5,500.00 (6,000 total)
Lav T500x0 (color up only)
Based on your proposed values -- 120 BB; total bank 121,500 (a little over 20 buy-ins)
Here's an alternative with a lot more bank and bigger stacks:
Lav T25x8=200.00
White T100x58=5,800.00 (6,000.00 total)
Blue T500x8=4,000 (10,000)
200 BB; total bank 165,675 (16+ buy-ins)
If instead you want with 1-5-25, here are 2 ways to do it:
Lav T1x10=10
White T5x58=290 (300 total)
Blue T25x4=100 (400 total)
200 BB; total bank 6,027 (15+ buy-ins)
Most bang for the buck
Blue T1x10=10
White T5x58=290 (300 total)
Lav T25x8=200 (500 total) or T25x4=100
250 BB; total bank 8,259 (16+ buy-ins) or 200 BB, 20+ buy-ins)
By making the blue the smallest chip and spreading them by 5x, I think for 3 colors that is more efficient. While not traditional tournament values, I think that gives you more flexibility.
Regardless, I think you can make a playable set for one table, and possibly 2 if you do it right.