No matter what route you take you will have to haul ass to get it done in a month. I assume that you already have got some long distance riding experience. It will be an epic trip so you may as well enjoy it and take a scenic way.
If I were you there are some places and roads that I wouldn't want to miss that are approximately on the way. Fit them in one direction or other.
In Colorado, hwy 550 north from Durango to Montrose; from Cody Wyoming on the Chief Joseph hwy, and the Beartooth Pass to Redlodge Montana, on to Missoula MT, thru Glacier National Park along the Going To The Sun Road; Alberta on the Icefields Highway from Banff to Jasper.
550 in CO is excellent.
I agree with trying to string things together, but it seems a lot of people are worried about time.
IDK as I've never crossed, but do you have to deal with the border and customs if you take the ferry? Also, the going to sun road is great, but it will take you probably 1/2 a day to do that one section. Lots of slow cars and you will probably want to stop yourself. After all, when will you be back in Glacier? I loved it there. There is more wildlife on the east side of the park. You could camp in Apgar one night, ride the road, and camp @ Many Glacier the next night. Make sure you have reservations though as they do fill up.
I would recommend at least riding through Yellowstone and along the Tetons from Jackson WY as well. You could ride up to Alamosa, CO, over Wolf Creek to Durango, north over million dollar highway to Ouray and Montrose, then north to Grand Junction, Keep going north to Vernal, Keep north to Flaming Gorge and up to Rock Springs. From there, on up to Jackson and into Teton and Yellostone Parks. I have heard about the ride north out of the park over Beartooth pass or something, but have not done it. I would then hammer down to Glacier (however you decide) and do some time there.
It depends on what your goals are. If you just want to see Alaska, slab it on the interstate. If you want to see lots of cool stuff, you're going to have to take the slower back roads. It also depends on how hard you want to push yourself, how often you will stop for pics and the like, and don't forget those pesky issues that may arise. We had 1.5 weeks for Teton/ Yellowstone / & Glacier. That wasn't enough time. Saw a bunch of all, but not nearly as much as I would have liked. I could easily spend 1.5 weeks in Teton/ Yellowstone, not including the time to travel there.
If you're camping, figure in time to breakdown camp, fix meals, etc. If you get to motel every night, you'll save time, but it's pricey. Fixing/ cleaning up meals also needs to be accounted for. Good luck and be sure to post a Ride Report!!!
ETA: Here's a quick google map you might consider. Covers the areas I talked about. This will be slower 2 lane highways instead of fast slab though: