In order to give you a simple "do it this way" answer, more
information is needed.
How long does it take to run those 5-6 queries on each
request? How many users are logged in at peak times? How much data
would you be storing in the session for each user? How much RAM do
you have on your server?
On one application, we've decided to go the session variable
route. The size for each users' session maxes out at 2.5 KB. We
have 512 MB dedicated to CF, but can easily scale up on the
hardware we have to 1.5 GB or more. At 512 MB, 2.5 KB per user
session, we can handle a little over 200,000 concurrent users
(assuming all CF memory could be utilized for session variables,
which isn't true). There are only 6,000 users total in our system,
so we have quite a bit of headroom.
Are you on CF8? If so, open up the server monitor, start
monitoring, profiling, and memory tracking, and log in with a
couple users (with your code setup to store all that info in the
session). See how much storage each session takes. Then look at
your server. How much RAM do you have? what do you currently have
allocated to ColdFusion? What's your peak concurrent user level? Do
you have headroom? Also, see if the benefits of storing it in the
session are even worth it (how long do those 5-6 queries add to
each requst?)