I am an administrator of a medium server farm with web server, index server and
database server. We currently have 4 portals setup for different divisions and
these are all accessed via the intranet.

I also administer a SharePoint Team Services environment that supports more
than 80 sites and over 1,200 users.

I have been given the task of migrating all these sites to our SPS server farm.
Which strategy would work better from both a security and performance
standpoint?
1) Create a new portal in SPS and move all the STS sites to this new portal or
2) Add a new web server to the server farm and move all the STS sites to the new
web server.

At one time we had thought about setting up a single SPS server instance to
house the STS sites The users who access these sites are located at multiple
domain locations. However, we want to be able to share other installed software
features available in our server farm that includes workflow and backup\restore
software.