To me JRPG is just a classification of style. Like Film Noir has certain characteristics instead of just calling them Crime Drama's.
JRPGs to me have cartoony-styles with massively overdone elements. Underage kids with.. Huge eyes, Huge hair, Huge weapons, Huge over dramatic movements, etc... Basically, if it looks like an anime cartoon... its a JRPG to me.
They hold no appeal to me whatsoever and when/if a developer attempts to incorporate some of these elements into a typical western RPG the effect is kind of like a slap in the face. The two genres have completely different appeals to two entirely different audiences. They should not be mixed.
You shouldn't equate elements of anime/manga/Final Fantasy that you dislike as being representative of the content or style of every game in the JRPG genre. I've watched some sci-fi anime series that are better - despite the size of the characters' eyes - than most of the shows currently airing on the SyFy channel.
I think that one aspect of JRPGs that you've ignored is that a number of them have interesting combat systems in which you actually do have to play it smart with your tactics and strategy. Combat can be a lot of fun and very challenging (without any silly button mashing), I don't think people necessarily mean that they want everyone to suddenly look like Sephiroth and to wield huge swords when they talk about incorporating JRPG elements (although maybe some of them do mean that - heh).
For example, at one point in P4G, I recall having to wield a golf club because it was the beginning of the game and the main characters - who looked like perfectly normal high-school students - couldn't scrounge up anything better at the very beginning of the game. Some of the weapons in P4G were humorous and quirky, but they were pretty normal in terms of size and appearance (not counting the intentionally humorous/goofy weapons like the Inaba Trout - which I loved because, honestly, it's pretty darned funny to smack an enemy with a pair of fish
).
That being said, I don't think any game should pander to fans of one genre another by trying to shoehorn elements or styles that doesn't really work. Like I said earlier in here (I think I did last time anyway), devs should really just concern themselves with making the best RPG that they can. If they do find sources of inspiration in a different genre and they actually work to make the game a better RPG, then great. I enjoy JRPGs and WRPGs, and unlike you, I would hardly consider it a slap in the face if certain elements from both genres were incorporated into a game.