Howdy
I have been loading 45 Colt, and several other cartridges, with Black Powder for years. I suggest you read my post over on The High Road that was referenced earlier. It is a long read, but I have tons of information there. In my not so humble opinion it is worth the read.
In a nutshell, what you are proposing is stuffing 10 pounds of stuff into a 5 pound bag. It won't all fit, and most of it is unnecessary.
Also, not all Black Powder weighs the same. So 35 - 38 grains of powder X may take up more space in the case than powder Y.
My procedure for loading any of the old cartridges with Black Powder is simple. First I determine exactly which bullet I want to use. I choose a bullet that has a very generous lube groove. Most modern bullets do not have a large enough lube groove to keep the bore of a rifle lubed with soft lube for the entire length. If the bore does not remain lubed for its entire length, the fouling will tend to harden near the muzzle into a difficult to remove hard cake that will affect accuracy. You will be shooting a revolver, with a shorter barrel than a rifle, so you can probably get away with a smaller lube groove and less bullet lube. See my comments regarding Big Lube bullets and Pan Lubing.
Once I have determined exactly what bullet I am going to use, I determine how much powder will be needed so the bullet will compress it by 1/16" - 1/8" when seated. That is the amount of powder I use for that bullet.
Yes, I have been compressing the powder with the bullet for years. It works fine. Not for precision long range shooting of 45-70 with a Sharps rifle, but for 45 Colt in a revolver it works fine. The issue is upsetting the base of the bullet when compressing the powder. For Long Range precision work I compress the powder with a compression die first, then place a thin card wad on top of the powder before seating the bullet. This keeps the base of the bullet from being distorted when seated. But for shooting 45 Colt out of a revolver or lever gun it does not matter much. I conducted some tests years ago with 44-40 out of a Winchester Model 1892. I loaded some ammo with a card between powder and bullet, and I loaded some without the card. No significant difference in accuracy. For a revolver, go ahead and compress the powder 1/16" - 1/8" when seating the bullet, after first deciding on exactly what bullet you want to use. I have information in my post about how to do that.
Regarding adding all that other stuff: When I was pan lubing regular hard cast bullets I saw that they did not carry enough soft lube to keep the barrel of a rifle lubed for its entire length with soft lube. So I started adding a 'cookie' of soft lube under the bullet. To keep the cookie from adulterating the powder, I added a thin card wad between the cookie and the powder. Accuracy suffered a lot. Turns out that the soft cookie was getting glued to the back of the bullet, and caused it to fly like a lopsided dart, ruining accuracy. So then I started adding a second card between the cookie and the bullet. This worked, but it was way too much work. That's when I discovered Big Lube bullets and I have never looked back.
If you read my post, be sure to make note of how I prepare a gun for shooting Black Powder.
It's all there.
P.S. you can use either FFg or FFFg with 45 Colt. I use FFg for all my Black Powder cartridges because then I only have to keep one granulation in stock. All other things being equal, you can expect somewhere between 60-100 fps less when using FFg instead of FFFg.