Adding 2nd Exchange server for remote users current access too slow

Solution 1:

According to your first sentence, these remote users are connecting via VPN. Does this mean there is no direct connection from the office in France to your main office in CA? This is important if you plan to implement a second Exchange 2010 Server in the France office as there has to be direct connection of some kind between the two servers. You will also need to implement a DC / GC in France if there isn't already one there.

Assuming you have a direct link between the two locations, adding another Exchange Server in France is straight forward. You will need to add the CAS, HT and MBX role in France. You can also sync Public Folders abetween the two servers. Just be aware that the first sync may consume a decent amount of traffic and take some time depending on the size of your public folder database.

I assume you will also move the mailboxes of the users homed in France to the France Exchange Server? I hope so as that would make the most sense.