switching root-fs

[Yury Michurin]

Hello,

I want to create a system, that will minimal boot, start only sshd, then I
connect via ssh, verify system integrity and mount an encrypted
partition(s).

What I have so far:
FreeBSD-7.1-BETA2
I've created one (1gb) a parition that mirrored over 3 drives, swap b
partition on the 3 drives, and another d partition that encrypted with geli,
on top of it there's a ZFS with the copy of
a partition, i can't make ZFS mount as / so i just made tank/usr mount as
/usr etc.

I hope you will provide me some information regarding:
1. So far i haven't noticed that the system became unstable, I guess it's
due the fact the proccess started before the new mount points are able to
access the "boot" filesystem,
    but should i expect any problems with init proccess?
2. How can I still access the "boot" filesystem i used the boot after I
create the new filesystems? Lets say i want to re-build world and I want to
sync the boot partition with the new system.
3. Is there any simplier method of creating a full disk encryption with the
abilty of providing the keys remotly over ssh/ssl?

Thank you for your time and assitence,
Yury.