First 15k - Tax Free
15k-30k - 20%
30k-60k - 30%
60k-150k - 40%
150k-1m - 45%
1m-5m - 50%
>5m - 60%
Ignoring the NI, this method would generate £13.5k more from someone earning £200k than the flat 30% tax would.
However, it also means that an additional £1.5k tax revenue is lost by putting the personal allowance up to £15k.
That means that just 9 people earning £15k a year would counter the extra £13.5k generated from that one person earning £200k, and there are far more people on the lower end of the payscale than up at £200k. Overall tax revenue is likely to be much lower than the flat 30%.

