Hello,
I am investigating the best way to manage a bitcoin wallet in a safe a private mode.
Hence I did some documentation dig on Electrum and Trezor combined with light research on deterministic wallets.

Now the questions:

I heard that everything can have a backdoor (NSA teach us), even a chipset, but I wonder if using the mytrezor wallet which require an internet connection to their portal is really protecting me against leaking the seed and give away the ability to potential attacker in an easier mode then the brute force that is mathematically unfeasible (even if every statistic teach you that probability is not protecting you from somebody who is lucky to get your seed at the first shot  ). I am also wonder the same question about electrum unless I can use something that protect me to do not give away my seed (i.e. offline) and allow me to sign transaction without any need to wire connect anything even a printer for a QR code. 

Regarding the privacy I believe that unless there is a way to detach/decouple the physical world with the cripto world there is no way to protect you against being tracked on block chain.
in the end of the day if you spend your bitcoin you connect yourself with somebody else. Tumblers/Mixers do not help. TOR has been hacked by the NSA so what for.
There are ATMs but as long as I can see they have all sort of tracking for your real Identity (even finger tips) which in my opinion is completely insane.

Thanks for giving me arguments on both questions