Personal experiences as well as opinions vary. Some like more powder than others. Some prefer conical bullets while others prefer round balls. Some like Chevy better than Ford. Others prefer brunettes over blonds.
Okay. I have been hunting deer, black bear, and wild pigs for over 30 years with a .50 longrifle. Not a Hawken, as you have, but a .50 nonetheless.
I use my muzzleloader through all the hunting seasons, muzzleloader as well as regular gun. (Think about it. You've surely heard of the .45/70 cartridge. Well, think .50/70 without a cartridge.) I use nothing else because I love the challenge of getting close to the game and using the old-style firearms.
My hunting load is 70 grains of 3F real black powder, under a patched .490 lead round ball. I keep all my shots at big game under 75 yards. On a broadside shot, my round ball (176 grains) easily passes completely through a deer.
I have never used any of the synthetic powder substitutes, but I understand that real black powder is difficult to find in many places, so you may not have much of a choice. With a percussion gun, it is my understanding that the substitute powders work fine. However, with a flintlock, in order to get reliable ignition, you need real black powder. The substitutes do not work well with flintlocks because they need a hotter spark than what flint and steel make to set them off. I have both a percussion and a flintlock .50 longrifles and use the same hunting load in both of them.
You will need a powder horn or flask, unless you choose the modern method of carrying individual loads in some plastic container. UGH - uncool.
You will need a powder measure. NEVER pour powder directly from your horn into the muzzle of the gun. Always use a powder measure.
You will need some attachments for your ramrod or a range rod. Range rods are stronger than a wooden ramrod, often being of steel or some other metal. Range rods are an addition, not a replacement for a ramrod.
For this you will need a ball puller, patch puller, and a jag. A breech scraper can come in handy at times, also, when cleaning the weapon - unless you have one of those awful "patent breeches."
A nipple pick for clearing the hole through the rifle's nipple.
Round balls or conical bullets, plus patching material and some form of lubrication on the patches. (if you're not out in freezing weather, a simple spit patch generally works fine.)
You will have to do a lot of shooting and experimenting in order to work up the specific load that your particular rifle likes best.
There is a plethora of information on this website about all of this. Take your time, read, and learn.