Armory's not windows only - works in Linux and I even recently tried an OSX version, but it's not "there" yet. I does fetch the blockchain using bitcoind, so if you've already done that, you're good. I really like multibit - even in the Linux machine I use for bitcoin it works great.
Truecrypt will help if your computer gets stolen, but if you get hacked while it's running (much more likely) then they'll be able to keylog you and get your bitcoins.
Consider getting VMWare Fusion and making a rather hardcore Linux VM to keep your coins in. It provides yet one more layer hackers would have to get into to get your money.
Thanks for your replies but this seems to have drifted towards a computer/client-based solution. Still wanting best way to generate paper wallet. And best way to encrypt a flash drive (although I'm now seeing that it makes sense to use Armory/Electrum/Multibit for local large sum storage). I probably will move towards Armory/Electrum/Multibit if I see myself needing to move significant funds around, but right now I just have big chunks in a safe deposit box and pocket change I use blockchain.info/mycelium/Satoshi client. I can see the use of Armory/Electrum/Multibit if you draw from cold storage frequently.
I use OS X primarily but run Parallels for Win 7 and Ubuntu and boot to a live dvd for anything dealing with keys. My qt is running on my old computer, just serving a node and don't really want to mess with the blockchain on my main machine. And I just use Truecrypt on my external backup drives to keep them off-limits.
P.S. Armory/Electrum/Multibit use RNG to generate their addresses anyway, why not do a 99 dice roll brainwallet?