If the caliber starts with a .4 or larger then you absolutely should be handloading if only for the money. 44 magnum is expensive and most stores don't even carry 44 special anymore. 38/357 can be a wash depending on your reloading setup and what you value your time at but big bore is where you actually save money while reloading which translates to being able to shoot and practice more.

If reloading you can have different loads but the same OAL, which means less mucking with dies, cylinder fouling and less free-bore. Load 357 to 38 special-level , 44 mag to 44 special levels, 454 casull to 45 Colt can all be good. I ended up with a shit ton of HP38 and H110 because that works for pretty much all my magnum calibers and their softer shooting counterparts.

I have a 45-70 BFR, and I use Varget for that. I got it as more of a meme gun but I honestly would recommend getting a BFR in a big bore caliber as they are made in the USA, well built, and come with an optional rail.