Damn, no mod points when needed. Most insightful (and IMHO true) comment I've read in ages.
Less is more ;)

The device would create the illusion of a standard habitat (sound, sight and smell) to those outside... but inside the cloaked frontier you'll perceive all wonders of my castle. The main point is that I need not to defend from those that don't intend on attack me. Since for the "world" there's nothing special in my castle, why would they want to spend resources attacking me?

I've been happy with http://cheapvps.co.uk/ (Xen).
FreeBSD VPS I don't know, I've always used Linux ones (Debian in particular).

Webmail as your primary MUA?! Are you kidding me?
I guess that's like saying skateboarding should be your primary transportation vehicle. Some people do it I suppose, but is it the best idea?
Get your own infrastructure and access your emails as you wish, like for example mutt on a remote terminal, or webmail (squirrelmail), or in any mobile IMAP client (my iPhone works great).
What about backups? What if tomorrow they change the policy of old/archived message?
I do have a couple of gmail accounts, but those are mostly for redundancy and seldom used by me.

I run my own mail server(s) and actually the number of spams I get is quite low with a daily average of 0.75 spams per day. That's down from ~20 spams a day before I enabled gray listing, RBL on my MTA and HELO restrictions.
There 0.75 spam/day emails are detected by my MUA's spam filter, meaning I tend to never have a spam email in my inbox!
You can find good/reliable VPS'es from $10/mo. that'll allow you to:

• Run your own DNS servers.
• Run your own SMTP/IMAP/POP servers (Postfix/Dovecote make a great combo).
• Run your own web server.
• Practice/learn sysadmin skills.
• No lock-in to any vendor.

I rather pay for my own VPS than pay Google for a freaking email account and/or their App Engine.

Give a man a fish...

To click icons and tick boxes you need to first understand the meaning of them, rationalize which of these elements fulfill your desired goal, and then activate the proper GUI widgets... each time to you're confronted with the GUI.

...Teach a man how to fish and he'll eat every day.

Using the CLI you need to know before hand the arguments/parameters that will fulfill your desired goal. It requires preparation (i.e. read the man page), but once you learn it it stays with you.

IMO CLI provides a more immutable interface, as opposed to GUI widgets that can and will change over time.

Software is a tool than when someone uses routinely its sensible to expect him to learn how to use it properly... for the rest of the human race there is Windows.

I couldn't be happier that the Linux experience is different from the Windows experience! Attempting to make a Linux or OSX experience Windows-er is as wrong, futile and useless as trying to compare a high-school romance with your spouse.

I attest that Y is a consonant in Spanish. Vowels are only five: A, E, I, O, U.

I have a similar setup, but got tired of content filters at the MTA level. My solution was to configure Postfix (my MTA) to abide more closely by RFCs (specifically for ELO|HELO commands) and install postgrey (`aptitude install postgrey`). Of course ensure you're not an open relay.
These measures decreased the number of spam arriving at my inbox by 90%. The spam that reaches my mailbox is handled by my MUA (Mail.app currently). The volume is low enough for me to check if its working. It does! As it was already commented read your mail logs... they make a fun read!
As for your sudden decrease of mostly spam incoming emails, some theories:
1. Some big telco closed port 25 for residential customers?
2. The recent DNS saga called sysadmins around the globe to check their servers and apply security patches and perhaps close open relays.