The biggest opportunity I see for ads on Farcaster right now:

1. At the end of a frame flow, when the frame has nothing left for the user to do, enable the frame dev to serve a *personalized* (and paid) recommendation in the frame
2. Enable frames devs to monetize their frames by adding an ad frame in the frame flow

Building FOSS via @frames, /open-frames to help decentralized social win. a16z CSX23. farcasterchannels.com farcaster.id

since frame actions include the users fid, you can do charge more for whales/high value users through personalization and better targeting. Perhaps for some users instead of paying to access the frame, they have the option to see an ad (a high quality recommendation), and for some other users they don't have this opt

and ads aren't necessarily traditional ads ("buy X today, it's the best"), but could just be suggested NFT mints or swaps that the user would enjoy ("30 people you follow minted Y, including Z, ... Mint here")

I would love to not see ads like the one traditional you mentioned. It will be annoying, i swear. 
But if it's nft or Coin then it's a nice idea