i really enjoy every part of the Pokemon games and i can feel as if i was the protagonist of the story. imagination is also needed when you play a game and you will feel the excitement when you play it. IMO, what makes you feel empty when play the game is because you play it in rush just like what you do normally. play it with your heart, feel the story. if you do that, i believe you can see what you normally cannot see in the pokemon franchise.
here is some thought about why competitive pokemon battle is forced to level 50:
http://www.smogon.com/dp/articles/mechanics_level50
Still doesn't really explain why your pokmon suddenly go all "new region pikachu". I'm looking at it from a "real life" point of view tho. If you were to eat until you're 100kg, you won't suddenly drop to 50kg just by entering the vegetable isle in the grocery store ...
Anyway, I'm not really talking about the story tho. Lots of people seem to think so. I'm just talking about what I do from start to finish. It feels as if I'm just constantly getting forced to do this and that, without having a lot of free will to it. SuMo was a bit different tho because you had some side quests which honestly needed some sort of note so you didn't forget. But even so you were very limited if you didn't first follow the story line. Take something like Skyrim for example, you could explore everything, totally ignoring the main story and do side quests instead and you'd still be able to actually see everything. Bad explanation I know but I'm hoping I somewhat make sense XD
Pokemon has felt less and less like a journey to me from Gen V onwards, because the narrative has framed it as being someone else's journey, and not mine. Since Black/White, the player has been a tiny cog in someone else's journey - this was especially prominent in Sun/Moon, which were entirely about Lillie - and the lack of character development for the player to match these still-faceless NPCs has made the whole thing feel rather stale. It's the journey of someone else that I can't get invested in. Despite the gameplay and progression of events not changing in any significant way, the narrative has changed dramatically for the poorer and now the games don't really feel like anything.
When I've finished the game I tend to put it down and forget about it. This could change with USUM, but the lack of noteworthy postgame content in the last two generations doesn't really encourage play time beyond accomplishing the main objective, at least to me.
A Pokemon iteration of Breath of the Wild would be disastrous. Whilst the freedom offered by the world was highly appealing, there was absolutely nothing worth doing in it. It was massive expanses of nothing with four miniscule dungeons and even less narrative than usual, and for a Zelda title that is saying something. Whilst that may work better for Pokemon in theory - you can populate the world with Pokemon, after all - a literal translation of that would make the franchise even worse, because then it would lose the narrative focus it has pushing (which, for some bizarre reason I cannot fathom, a lot of people really seem to enjoy) and there would be a lot of empty space.
I'll say the same here, I kind of talked about it in response above. But I'm not to much about the story of pokmon in general it pretty much has the basic setup of evil group that wants to use pokmon as tools that you need to defeat and blablabla. It was interesting for the first 2-3 gens (I honestly see gen story 1-2 as 1) but after that I just started to go through the game not even paying attention to the actual story. For me it's more about exploring and such which has always been extremely limited until you finish main story at least once which most of the time leaves you without the will of going back to previously visited places.
I honestly like Breath of the wild, as a LoZ fan I gotta say that I loved the freedom. Then again, I'm also one of the people who really liked Hyrule warriors because I liked to not just be Link but also have some fun with other characters that I love from other LoZ games. I think having an open world with an improved battle system from Pokkn would be really nice. Only problem I have there is that the thing I like in Pokkn is the lack of stats/levels/weaknesses, it makes the game slightly more equal, but it's impossible to really put that into any other game because how do you go by evolutions?! What I was hoping for was a game that's somewhat closer to the anime and thus somewhat more "realistic" (not really the word I was looking for but it'll do XD)
whether or not pokemon games have felt less or more like a journey depends a lot on what you feel like your general perspective of a proper journey/adventure should be to begin with.
Meyneth has mentioned pokemon games feeling less like a journey from Gen V onwards, but really, it's not like Gens I-IV were super flawless perfect pokemon games in that aspect; the first two generations didn't have any sort of narrative to them at all. Whether or not you feel that's a good thing depends on your preferences in narrative in video games, though. In Gen III, the NPCs were insignificant and not really memorable aside from Team Magma and Aqua, so there was no one to really get attached to besides probably May/Brendan (depending on the protagonist you chose).
Heck, if you want to be really pedantic, other NPCs didn't get a chance to get so much of a background until Gen IV, not Gen V. While Gen IV didn't revolve around Cynthia nor Barry by any means, the generation was still the start of Game Freak deciding to give other NPCs more character and depth; Cynthia via her own background as a researcher and her grandmother, and Barry via his own father who is a Frontier Brain.
pokemon games, of course, have always been about the player's journey. that never changed regardless of what
anyone with nostalgia goggles say about it. despite SM being "about Lillie", anyone who paid an iota of attention to details in the plot objectively would tell you that the player is a crucial part of the story. after all, who was it that got to take care of nebby at the end of the day,
and beat Lusamine, upend Team Skull, and knock sense into Gladion? It wasn't Lillie, it was the player. who is it that becomes champion at the end after going through all they go through (and keeps the title to defend it)? hint: it's not lillie.
personally, recent generations have finally given me a reason to
care about other NPCs, about the people who I'm going on a journey with and giving my journey some purpose. in early generations it was only about the player, and not in the good sense because every other character bar the rival and evil team leader were all faceless, forgettable npcs to begin with. no one with any backstory in the slightest until Gen IV/Gen V.
tl;dr what defines a satisfying pokemon journey to me isnt just what the player does; it's what the other characters do. if they're going to be a part of my journey, then what's the bigger reason? give them depth, fluidity, emotion, things like that. give me a reason to care.
ultimately making npcs more central to the player's journey is a hit or miss decision anyway because that relies entirely on whether or not the player would be fond of that npc's development and character to begin with and as such, it colours their view of the game as a result.
I mentioned a few things above so ... uhm, plz go read XD
Continuing on from there. I personally fell back "in-love" with pokmon with OrAs because of how free it felt after part of the story. You got your Latias/Latios to freely roam, you got secret bases to share and explore ... but again that's where it stopped. Still, ever since gen one HM makes it all extremely limiting. Because of those you're forced to follow a narrow line. This again changed with SuMo but HM's now got replaced by ride pokmon which is definitely better than having HM slaves but it still makes you follow a narrow path and doesn't allow you to do things at your own pace.
I'm glad to see that USUM has some more to offer with going through portals with Lunala/the lion thing (forgot his name) and Mantyne surfing but it won't affect you that much until you completed the main story and become champion ... again.