I would like to see:
0 to $25K single income, no taxes
$25K to $100K single income, 15% tax rate
$100K to $1,000,000 single income, 25% tax rate
$1,000,000 and up single income, 30% tax rate
Maybe a progressive scale from $25K income and up, 15% to 30% tax rate.
Use a anonymous tip reward system to find tax cheats.
Whatever system you decide on, KEEP IT SIMPLE!