Certainly, no one worried about spoilers is likely to read this thread, but if you do, you have been warned!
Hmmm, in order of appearance, my two cents (which is probably all that it's worth, if that!), expounding on a few of the comparison points:
Frodo always seemed a little more hagridden with cares than Bilbo did, which is mostly likely because The Hobbit was written for children. We get to know Frodo over a longer period of time than we were offered with Bilbo, for sure, so his early concerns have more time to bloom on the pages.
Similarly with the call to adventure. Unlike a hastily scratched wizard mark on the door and a busload of dwarven visitors who must be fed, watered and entertained while Bilbo tries to get his head around their story, Frodo gets a stern warning about keeping the ring secret and safe from Gandalf almost 2 decades before his call to adventure, and even then gets the better part of a morning devoted to a history lesson about the ring (again, from Gandalf exclusively if you ignore Sam's gardening) before ever having to decide about having an adventure.
Fair enough about being waylaid, although the dwarves and Bilbo put their heads in the noose by trying to pilfer from the Trolls, while Strider and the hobbits were doing everything in their power to avoid the Black Riders.
As for Elrond and Rivendell, well, if one must travel to the eastern side of the mountains, one has to cross them somewhere. Might as well take the route that benefits from Elrond's advice. Tolkien even said so in The Hobbit, and took his own advice in The Fellowship of the Ring, not that the hobbits and Strider really had any other alternatives. The difference is that the stop in the Hobbit (again, because it's a children's book) was more like a "Hey, it'd be a good idea to stop in Rivendell to get those runes read", while in the Fellowship Rivendell was a tactical destination, and the only hope of shelter from the Riders that side of the mountains.
Good point about the storm, although in The Hobbit the storm (and Storm Giants) technically forced them further INTO the mountains (and ultimately thru) while Caradhras (and Saruman) tossed the company back like yesterday's junk mail.
Re Moria, Gimli would be rather unhappy to have the Goblin caves even mentioned in the same breath, much less so associated, and while you can definitely make the argument that Gandalf put an end to both, the Great Goblin's end was an afterthought, while the Balrog cost Gandalf one version of his Maiar self (yes, I drank some of the Istari origins cool-aid!), completely changed the plans laid by the Council of Elrond, at least as far as the entire Fellowship was concerned, AND was the catalyst for allowing Manwe, Varda, Illuvatar or whomever had their hand in the mix to serve Saruman his comeuppance for betraying their trust (more Silmarillion historical cool-aid and supposition!).
Your other points align more closely, but if I'd taken all the time and trouble to create that many calendars, languages, alphabets, MAPS, etc., I'd certainly use them again and again. Who can therefore blame JRR if he had favorites among his many creations (whether he admitted it or not)?