I thought I would solicit your help with this as I am having trouble finding the data.

I am trying to find out what load/powder combination would give me the greatest muzzle energy and the lowest pressures. I would also like to keep the round subsonic.

Any help with this would be greatly appreciated.

Greatest muzzle energy, but keep the bullet subsonic? In the 41 Magnum that is something that just isn't often done, but to do it I would recommend trying cast lead 40 caliber rifle bullets, 300-350 grains. But you will have to come up with your own powder loads as you won't find any for these bullets in the loading manuals.
Heaviest bullet normally used in the 41 Magnum is the 270 grain WFN, but it needs to go supersonic in velocity for proper stabilization.
The load I used for cowboy shooting is subsonic, 5.0 grains of Titegroup with a generic 210-215 SWC bullet, but it is far from maximum muzzle energy.

Just load around a 210gr lead bullet with 7 to 8 gr of Unique.

If you need more "power" than this, forget subsonic.

Maximum energy, and subsonic....
So, are we shooting buffalo at night with a silencer?
If you give us an idea how you plan to use the load, we might be able to give you more help.

I've just gotta say a few words about my experience with TiteGroup and Unique in my Blackhawk 41 mag. TiteGroup burns a lot cleaner and produces smaller groups in my gun. Load is 6g TiteGroup and 210g "Friends Woods Bullets" cast SWC at aprox. 950-1050fps. I believe the difference is TiteGroup is not as position sensitive as Unique. I've used Unique for many years and am slow to make changes but TiteGroup is clearly the better powder for my 41, 44, and 45 subsonic cast bullet loads.