NAS setup, should I do it?

So i have recently purchased a raspberry pi for setting up my own NAS server, mainly to collate all my data(which is present inside multiple hdds and ssds) lying across the house.

Now I am in doubt because i feel that its much safer to keep the media on a offline ssd rather than a DIY NAS. I do have some ideas for its security but it would still not be full proof.

What are your thoughts?