Do you start at Miami or do you start at Montreal?
Anyways, if you ride Greyhound in the Northeast, you have a very high chance of riding a painful bus. I suggest that you ride Amtrak, Peter Pan, or New Jersey Transit in the Northeast. DO NOT ride Greyhound in the Northeast unless it is a through schedule to/from faraway (I mean really far away) places. Don't ride Greyhound in Michigan. High chance of getting old demo equipment (which is crap) or getting tortured. Ride Amtrak instead.
Evade Greyhound and Megabus routes that use torture equipment. AFAIK, the only Megabus route that doesn't have Double-Decker Torture is the Lakefront-operated Buffalo-Cincinnati-Atlanta route. You might use that route, though I doubt 'cause it's north-south. Why are double-deckers bad? Well, they have terrible headroom, ride poorly because they're so tall, and have no overhead luggage storage.
I'd make a few changes to your itinerary. To save money for Torture Avoidance in the Northeast, change San Francisco-Portland. Make an overnight in Sacramento and ride the daytime Greyhound to Portland. Yeah, it's a long ride, but it's daytime with top-notch and has low chance of torture. Keep the PNW bus rides. Better watch out with Yellowstone, you'll be riding SLE and I've never found out anything about them. Salt Lake City-Denver, change to Amtrak for the scenery. NOT to Greyhound due to high Torture Chance.
In and out of Detroit, change to Amtrak to avoid torture. In and out of Morgantown, watch out, that's definitely not Greyhound. I'm not sure who, but maybe Barons'? Pittsburgh-Washington, better change to Amtrak unless you can get onto Greyhound's Chicago-Washington schedule. After Washington, you should not ride Greyhound anymore. Everything between Washington and Montreal that you could ride is Torture Daily. So go with Amtrak, Peter Pan, or public transit like New Jersey Transit. Once you get past Washington, everything "GLI" is immediately eliminated. You'll spend more money here, maybe a lot of money, so it would be best to save money elsewhere like I pointed out above.
Oh yeah, if you've already reached Austin, you might want to go to San Antonio after all. Either way, you can catch a train (Amtrak Sunset Limited) from Austin or San Antonio to El Paso, then Greyhound to Albuquerque. That'll give you some nice "Wild West" scenery. Another way is that if you want to visit Lubbock, Texas, you could take Greyhound straight there from San Antonio. Then Lubbock to Albuquerque. The former is a rural countryside ride Texas-style and you might like it.
I know you're tight on time, but you can cut Morgantown and maybe Atlantic City.
Also, since you're going up Mississippi, you could think about this rural line: http://deltabuslines...chedulefull.php. But beware, they only have D4505s, and you know I don't like those!
I know you won't get any overnight Amtrak sleeper rides, but when you ride overnight, you don't see anything and with all the stops you want to make, it's just not a good idea.
Edited by Swadian Hardcore, 11 January 2015 - 06:11 PM.