Site Architecture - Project Management Portal - One Site or Subsites?

Question

I am a new SharePoint Admin working for the local county IT department. We would appreciate some guidance on architecting a comprehensive project management platform in SharePoint 2013 On-Premise.

Requirements

• Strong need for content roll-up (aggregation) and relationships
• May have 500+ projects in the near future

Our steering committee members are in one of two camps:

Option 1 - One Site For All Projects

• The site contains a Project list. Each Project is an item in the list
• Other content, documents, list items are associated with individual projects with metadata

Option 2 - Subsites For Each Project

• Each Project has its own web
• Each Project web has its own lists and libraries for content

Questions

• To anyone with experience implementing such a system; is there advice you could offer?
• What are the recommended best practices when determining whether to use subsites or to keep everything in one web?
• If subsites are chosen, what pitfalls should we be aware of when managing potentially hundreds of subwebs?
• If a single site is chosen, what pitfalls should we be aware of when managing lists and libraries with potentially hundreds or maybe thousands of items?

Answer 1

Frist of all, I would not go with Option # 1. One list for 500 projects( thousands of Documents) along with One Document Library against a lot of documents. It will be unmanageable after a short time.

Now I would make the decision on the basis of the following information.

• How many departments / team maintaining these projects. One for all or small teams.
• expected number of List Items & number of documents
• Number of users
• Unique permission?
• expected size of the site.

One site with 500+ subsite in it, not a bad Idea but again,

• hard to manage 500 site collection
• database size can quickly become too large to operate efficiently
• a single site collection can be a permissions nightmare
• Backup and recovery bit hard
• Performance may be an issue.

I am thinking another option.Create Multiple site collections and distribute the Load evenly on it.