Hi Tech,
The Netcraft toolbar should be the number one option, because of several reasons. It does not weigh heavy on the browser, it does not distract you, only and only then whenever you are likely to stray off to a phishingsite or similar malicious site. Then it starts to bark to keep the innocent sheep away, so to say, and blocks it from further visiting, (or you must be stubborn and override it). Second consideration, even the newest anti phishing features inside the Mozilla FF 3.0 test browser are "crappy" and insecure.
Concerning RefControl, this l is another add-on that does not interfere with anything and you can tune it from down under in the browser bar and tweak its settings. Does not weigh, does not interfere with other extensions. Just install and forget about it until needed.
Or you could install No-referer 1.0.1 enabling you to send no referral info whatsoever when you open a new tab.
Fire Encrypter 3.0 is for coders and webmasters, and those that want to encrypt on the fly. Not essential security wise.
TrustWatch can be a companion and works beautifully alongside finjan, so why not actually? You can have it with big or small images even.
I have a couple of years experience with these security add-ons working happily alongside each other and together, no sweat, so what is holding you back?
I even started to put Netcraft to the test using the SLQ injecting tools on the so-called Hackbar extension for Flock (no, do not install that one), but this brought me the impression that Netcraft toolbar is one of the "golden essentials", like NoScript is and will be. Netcraft toolbar blocked the URL even when a little a was placed at the end, really like you say "imposant".
The best add-on for them all is Febe or Firefox Extension Backup Extension, to keep all you extensions and add-ons back-upped at some place of your choice on your comp, in My Documents for instance.
You can set it to do its back-ups automattically at Monday 1.00 PM for instance. Enjoy these security extensions,
polonus aka Damian