Good idea regarding the advertising.

My idea of a business model that could monetize without risk of losing its ethos:

1. Build a pruned capable relayer implementation for Umbrel and the likes (TOR based).
2. Build a Relayer Pool TOR based (like the mining pools) so users willing to share revenue put their relayers to work, in exchange, the relayer pool advertising revenue is shared proportional to the size of the  storage added with reliability above a minimum threshold to qualify. (low bar or it would defy the decentralization ethos)
3. Build web clients and share them over IPFS, current ones are all investments looking to monetize ASAP so they won't work for the Nostr ethos.
4. Build mobile apps FOSS and with TOR built in by default, sacrificing some features always better than sacrificing privacy.
5. Ask Minibits to join the party, having ecash-lighting as the default solution seems only logical (until Ark become a thing)

I have been drafting this to a friend that is fired up to build this no matter how long it takes and is willing to fund it... Although if he adds TOR by default, monetization will be harder and reliability lower, trade offs...

On a funny note, I told him that if he waits 3 to 5 years a simple voice command will build the code for him almost free using current language models (oh yeah, the buzzword is AI)... 

It is a while I don't write a line of code, just type a pseudo code query and get really decent code in seconds, minor changes and is all good, each day less outsourcing needed, almost zero already... The IT industry is going through a revolution good for corps and entrepreneurs bad for coders ... interesting times ahead