Suggestions on carrying it all!

Well, I was very inspired by Inside Analog Photography podcasts and ended up purchasing a medium format camera (Pentax 645) to add to my arsenal of film cameras!

So, the dilemma works in two sections. First, the gear I'm trying to hold:

Pentax 645 w/ 75mm F2.8 lens, Pentax SF1n w/ FA31 Ltd and FA77 Ltd lenses, Pentax K-7 digital (as backup), accessories, film, etc.

Second, the issues I'm trying to avoid:

1) Sweaty back - I tend to work up a sweat really quickly. The 645 is really heavy gear and just does a number on me and I end up sweating. Backpacks seem like the best idea but I get a really sweaty back with them!
2) Sore shoulders - My shoulders tend to get tender when I carry a lot of gear. I thought about putting all my gear on a thinktank belt setup, but the weight of the 645 on one end is going to pull my pants down!


I do wedding, portraits, events and general "life" photography and I work in a documentary style.

My current setup would be :

1 x Adidas sling bag - carries Pentax 645, accessories, and my other amenities.
1 x Photo Runner (via thinktank belt pack) - carries 35mm film system.


Anyways, looking for any suggestions.

I have a Lowepro minitrekker and I can get my 645N with 75mm, 120mm (big lens), PZ1p with zoom, and maybe the fisheye in it. The PZ1p is about the same size as the K-7. I don't think I have a chance of getting 3 bodies in it and it usually weighs around 20-25 pounds with all I do have in it.
I'm also looking for the "perfect" camera bag and I'm pretty sure it doesn't exist.

http://babyjogger.com/perf_jogger_lp.aspx

John Powers