vechain/thor

Hi. Just wanted to ask a question. Before that, I would like to apologize if this is not the correct medium for this.

I am looking at the tech and want to start on a project. I've done some reading on Thor and the apis, but before I dive too deep, I wanted to consult already knowledgeable people if this is possible:

I am thinking of making a messaging app that uses the Vechain Blockhain. So, a mobile app that connects to the Vechain Blockhain like the Vechain Wallet app.

You will write a message. The frontend, i.e. the mobile app, will encrypt this using the public key of the recipient address you are sending to. This encrypted string will be written on the blockhain as a VTHO transaction to the recipient address (in the data segment). The recipient will open their app. Download the transaction information, including the data segment. Decode it using their private key. Read the message on their mobile device (obviously in plain text format, like a normal text message).

Of course, there is a few more additional steps that I'm skipping over in terms of user signing in (perhaps their mnemonic phrase) and they would be consuming 21 VTHO minimum for each text message they send.

Also, obviously for push notifications, I would have to be either using another 3rd party app / backend server to notify the users when a transaction(message) arrives to their address.

Before I get started or raise my hopes for this idea, I wanted to check if people see any major issues when it comes to implementing this. Any help is appreciated and thank you for your help.