As mentioned earlier, Scenarios have been given an important performance increase. The devs have more on the tweaks for Scenarios:

It's been an exciting few days here at the Studio as we rolled out 1.01 and added many new hotfixes in addition to the update.

One of our primary focuses with 1.01 was to improve performance in Scenarios. Thanks to your feedback it looks like we hit our mark and Scenarios are now running smoother than ever, especially on high population servers.

Your performance in game is still our top priority and we'll continue to listen to your feedback and address your concerns until as many people as possible can enjoy the glory of WAR.

Click here for an thread in our forums discussing Scenario performance.