Yeah my biggest win I think is close to your top end field size. I played 13000 players, managed to get a first in $16.50 bounty and got $2100. Had loads of reaching 1 or 2 tables from the final table, and some final tables but rarely hit the top 5 although they tend to be quite big fields.
Played a 128 player tournament on
888 recently $12 entry, got a first on that but seemed like a breeze to the much bigger fields I am in on
pokerstars although need to try a few more that size. It still paid $500 which is still 25% of the payout of the $16.50 I played but with 10% of the players. I find you do need to win more flips and a bit more luck in big fields but the pay is heavily weighted to the top few spots don't know if I should through more smaller games in.....however late registration often for 2 hours makes it hard to predict the amount of players except trying to base on the guarantee.