Is it better for performance to separate a node web app into separate server blocks?

I'm putting together my first relatively complex web app, I don't expect it to get a ton of traffic, it's more of a hobby app, though I want to use a good architecture pattern that allows the public facing aspect to not be interrupted by my admin type work (eg working with the API, image manipulation stuff, emails jobs, cron jobs, etc). Does the below look appropriate? Any suggestions on a better pattern? Is it worth separating all this out? Or if I'm not doing a ton of admin work, and don't expect a ton of traffic (say 1000-2000 visitors a day), is it not necessary/worth the complexity to split everything out.

I was planning on using DigitalOcean and put the various parts of the app on separate server blocks. For example -

Public facing website: (e.g http://www.myapp.com default port)

• Express app
• Routes make requests to the API
• Serves static Jade templates (not much interactivity)

Private Admin website: (e.g http://ift.tt/1aqgXga separate server block, separate port). This will really just be used by me.

• Another Express app
• CRUD interface for the app, using the API

API: (e.g http://ift.tt/1Sforlv separate server block, separate port)

• Another Express app, nothing client-facing
• Uses MongoDB