WP Ultimo allows you to select which plugins are allowed for each plan, so WP Ultimo will automatically activate/deactivate the plugins based on the purchased plan.
Also, WP Frontend Admin integrates perfectly in this case, because it has the option to select which WP Ultimo plans are required for each dashboard page.
And you can select in the WP Frontend Admin settings if you want to hide pages when the current plan is not allowed, or redirect to an upgrade page, or show an upgrade message.