Looks very solid , below are a few things that you can add :
Additional browser protection:
1.Site advisor :
WOT (Free) -
link
To help you avoid malicious sites you can use Web of Trust (WOT) a website rating browser plugin. After you add it to your browser make sure you only visit websites rated "Green" by WOT
OR
Norton Safe Web (Free) -
link
Norton Safe Web is a new reputation service from Symantec. Our servers analyze Web sites to see how they will affect you and your computer. Then, using the Norton Toolbar installed on your PC, we let you know how safe a particular Web site might be before you view it.
2. Increase your privacy :
Ghostery (Free) -
link
Ghostery is your window into the invisible web – tags, web bugs, pixels and beacons that are included on web pages in order to get an idea of your online behavior.
Ghostery tracks the trackers and gives you a roll-call of the ad networks, behavioral data providers, web publishers, and other companies interested in your activity.
You can read
here a review on Ghostery
Additional On-demand scanners:
Emsisoft Emergency Kit (Free) -
link
With the Emsisoft Emergency Kit Scanner you have got the powerful Emsisoft Scanner including graphical user interface. Search the infected PC for Viruses, Trojans, Spyware, Adware, Worms, Dialers, Keyloggers and other malign programs.
Run the Emsisoft Emergency Kit Scanner with a double click on a2emergencykit.exe. Found Malware can be moved to quarantine or finally deleted.
VTzilla (Free) -
link
VTzilla is a Mozilla Firefox browser plugin that simplifies the process of scanning Internet resources with VirusTotal. It allows you to download files directly with VirusTotal's web application prior to storing them in your PC. Moreover, it will not only scan files, but also URLs.
The scanning options are embedded in Firefox's context menu and download dialog, making the analysis process as easy as clicking a single button.
More Info
I see that you're using a VM as Sandboxie.......Why don't you use Sandboxie? It's as safe as a VM but starts faster and works good on 64bits.