I have used the 2-3% rule on large events, >$20,000.
Example 1) In 2 Stardust $100,000 events I took $2000
out of my wallet and also left the cashable table chips. I forgot
the table chip amounts but one was about $1300, the other was about $900.
I agree with K.S. on the smaller events generally $400-500 on $10,000,
also up to 10% on weekly events paying 1-$2,000. I saw the same dealers
week after week, so I thought the higher % was justified.
If I'm in an invite only event, I tend to shade the tips upward and spread
them around (i.e. , not just the dealers).