SharePoint 2013 Farm Architecture – 100 employees

We currently have an intranet running SharePoint 2007.  We have a farm of 3 SP Servers:

2 WFEs

1 App/CA/Search indexing

Separate SQL cluster for the databases.

We are currently planning on project to move to SP2013 and attempting to decide if we need to keep 3 SP Servers or if we can go down to 2.

We have 70 – 100 employees and are a very document centric organization.  SP Search indexes our full farm and fileserver.  We utilize SP for most tasks (document libraries/lists, etc.) and have a few custom SP solutions/applications.

Can our 2013 Farm consist of 2 WFEs with one of those also acting as App/CA/Search indexing without degrading performance?

Thanks