I'm a little bit perplexed in understanding the difference between multisite and local plugin activation. Some plugins also act differently. Some can be turned on in the network control panel but require being activated locally on each site because they have per site settings. Others are set in the network control panel and are active on all sites.
For example, if you use the WordPress SEO plugin by Yoast and turn it on in the network plugins panel, you still need to turn it on for every site to enter unique settings. Is there any point to turning it on in a central location? Does this create additional unnecessary overhead?
In addition, others like Simple Local Avatar you can activate in the network control panel and will work on all sites but will not appear in other sites (like the multisite manager plugin). You wouldn't know they are there unless you go into the network control panel.