Release management: Where should I put my provisioning code?

Hello everyone,

I work for a company that uses SharePoint 2010 and is planing to migrate to 2013 very soon.

This company has 3 environments: TEST, ACCEPTATION, PRODUCTION

Most of the sites they are asking are very straight forward (no customizations needed) but they have the following requirements:

1. The site needs to be developed on the TEST environment according to their requirements
2. The site needs then to be transferred to the ACCEPTATION environment and then to PRODUCTION
3. Every update to the site needs to be done the same way without loosing existing PRODUCTION data of course

As a matter of fact point 1 and 2 can be achieved by a simple backup / restore strategy; point 3 though can't since it would erase PRODUCTION data.

I see three ways to achieve the process for the moment:

1. Create PowerShell scripts in order to do the modifications on the site 
2. Create a solution with feature event receivers to do the modifications on the site
3. Create a console application to do the modifications on the site

I have been using method 1 for a year. It lets the provisioning custom code outside the SharePoint farm but it is not C# and I am much more efficient in C# and Visual Studio.

I like method 2 because it is written in C# with Visual Studio. The issue I have with is that it puts the provisioning custom code inside the SharePoint Farm and it is not very convenient for migrations.

I am considering method 3 because it lets all the provisioning code outside the SharePoint farm and gives the benefit of being in C#. 

In case of sites with coded customization (WebPart, EventReceiver, ...) I am also wondering:

• Should I leverage the fact I have to create a SharePoint solution and embed in it the provisioning code? (and so complexity my solution)
• Should I keep in the SharePoint solution only the customization and use solution 1 or 3 for the provisioning code?

What do you think? Do you have another (better) method to do this release management process? I would like to make the migration to 2013 as painless as possible of course.

Thanks in advance for your insights.

Regards

Carlos