I buy chuck roast, too. It really gives you the best flavor and it's probably one of the cheapest. I always buy Angus (it's more tender) beef though. A local grocery store always runs them buy 1 get 1 free, so it's like $12-$14 for 2. I think this cut of meat is fine after being frozen, too. I can't say that about all meat though.
I never buy bouillon cubes. Instead I buy a base. I use beef for roasts and chicken for chicken, etc....
I used to brown my meat, but I've found that's not really necessary. I just put the roast in a pan on the stove (no slow cooker here), toss in 1 minced onion (run thru food processor) and add the soup base to get the desired flavor. I bring it all to a boil, cover and reduce to a simmer afterward that. I let it cook for roughly 3 hours. An hour or so before it's done, I add potatoes and carrots. Keep in mind, if you want a gravy (and I don't make gravy if I have potatoes and carrots on the pot), the carrots will overpower the broth and your gravy will be nasty. If you want to make gravy, add more water to the pot initially, then take out the amount you need for gravy prior to adding the veggies.
Now, if you want a fall apart roast. IMO, you're not going to get it from a crock pot OR on the stove. You need a pressure cooker. You will not be able to add the veggies to the cooker though, so make this when you want mashed potatoes and gravy. Your roast will literally melt in your mouth. When cooking in the pressure canner, I again add water, base, onion, and of course the roast (only chuck here) and it'll cook like an hour to an hour and a half. Depending on when you want it to be done.
Here is a link to the base I buy, but there are many types. The one I've been buying requires refrigeration after opening, but there are many out there that do not. I can guarantee this one has one heck of a flavor. We have an Amish run store and I don't know the brand they sell (they package it in a way that you can't tell), but it's every bit as good and it's cheap!
http://www.superiortouch.com/btb.htm