I'm new to rails have been searching for deployment guides on the web - it's quite fragmented. I see some which recommend deploying as a sudo enabled user. I was thinking you would create a user with no sudo powers to run the app for security reasons. It would need it's own home directory for RVM and bundler but having sudo powers seems redundant and a security risk. I'm doing this all manually as it's a tricky beta level application and deploying it is not yet straightforward, so capistrano would only be a layer of obfuscation at this point.
I'm using thin as the server with Nginx as the proxy and redis and Postgres as the database. Clockwork and sidekiq as well.
Capistrano seems like a lot of work even for a small project but it's worth getting setup anyway if you have hopes of the application growing (and thus the complexity of deployment increasing).
I personally like the idea of separating the distribution specific Ruby available (and gems) to an RVM deployment specific to the application. Furthermore, requiring bundler to manage gem dependencies and ensuring compliance is invaluable. I wouldn't suggest enabling sudo for that user; it'll expose the whole stack from HTTP requests to root level OS control. Applications shouldn't require administrative access, deployment scripts might.