Yes. That's correct. You would've had to find a miner to include the transactions in the blockchain. However, in upcoming versions, setting output as OP_RETURN

Yes. That's correct. You would've had to find a miner to include the transactions in the blockchain. However, in upcoming versions, setting output as OP_RETURN (which basically allows you to embed additional data) will be a standard transaction type, but immediately prunable. Hence, for the 'currency' part of Bitcoin these transactions won't form part of the bloat, but nodes that want to keep track of it, can (https://bitcoinfoundation.org/blog/?p=290 https://bitcoinfoundation.org/blog/?p=290). Miners will still choose whether to include them or not (being a good citizen and adding a tx fee is still recommended), but now other nodes will relay them so they can find their way to a miner. Other Bitcoin developers can correct me if I'm wrong.