[Game Idea] Hi ! Anyone willing to give me feeback on my ideas ?

As the title says, I've had an idea that I want to develop to see how far I can go with it, and to challenge myself to actually do something productive for once.

Tiny bit of context: I've got little to no experience when it comes to Rom Hacking, my skills have nothing to do with programming or such (only things that I do that come close to a rom hack is music creation and writing), still my idea is pretty fleshed out in my mind as I had it for quite a long time now.

Now what's that game about ?

The region is Helikos (Greece of our world), a region that has no clear link with any other regions of the Poké World, in the sense that it is not part of the Consulate (political setting of this PokeWorld) due to quite a few things we're gonna go over soon enough. The Pokémons you encounter here are not very different from the one you can encounter in the other European PokeRegions, but the region being in between Kalos and Hoenn, it is not so rare to encounter Pokémons from the asian PokeRegions. The unique ones are mainly regional variants and mega forms.

The story is Callum's story, champion of the Sinnoh region fallen from grace due to the organization of rigged matches. Callum faked defeats in official matches in order to be able to sustain his sick father that is in deep need of medical attention. The Consulate (which is, to make it simple, a political body that acts as both the head of state AND a global Pokemon league) originally sentenced Callum to serve time in jail, but his specific situation was deemed as exceptionnal (and not gonna lie, Cynthia is a big part as to why the hell this guy dodged that bullet), he was offered an alternative to pay back his mistakes. Callum was given the choice to either serve time, or go and assist the CBF (Consulate Blue Force, equivalent of the UN) to securize the Helikos region, currently held by a criminal group reffered to as Pure Helika (no, they're not just the generic bad guys). Callum accepts, and is sent in the region, where he is gonna be investigating and fighting alongside many talented individuals that could be from the CBF, natives of Helikos, and even an old friend from the Pokemon franchise that you'd not expect (Imma say it anyway, Silver from Gold/Silver is a lieutnant of CBF).

The game mechanics would be for the most part quite similar to what you're used to, however here are a few things that I'd like to be a thing here:
- Multiple dialogues options that have an impact over the story (e.g, one of the main objectives is to establish a League within the region, and your choices might impact who becomes a gym leader and such)
- Open-world: the goal is to identify and take down various mob bosses all over the region, that you might be able to take down in any given order if you're not afraid to venture into dangerous areas
- Permanent death: You'd be able to switch this on/off, but I would mean that some boss fight (mob bosses) and dangerous wild Pokemon could actually kill your Pokemons. Story wise, some characters will die and some might if you make poor choices, and this aspect can't be turned on/off.
- CBF Squad: You'd be able to access strategic battle zones with companions you made along the way, with each their special ace Pokemon and aptitudes.
- Relationships: Tying with the previous, you could make actual friends within your squad and/or other characters througout the game.

More specific gameplay features would comprise of:
- Up to gen 8 mons
- No HMs
- Unlimited TMs
- Following Pokemons/Squad

I know that all of this is TREMENDOUS work, but I'm mainly seeing this as "Reach for the moon to land in the stars" as in I'd do the best I can and see where this takes me. My goal is to mainly develop myself more than developing something for the others.

Any thoughts ?

Before I get into my thoughts, you should know that most fan games are made as a rom hack or as a standalone game. The rom hack section isn't this forum but still inside the Fan Games section. This section is mainly for pokemon essentials using RPG Maker XP. If you want to make a rom hack you should look at resources in that section but if you want to use pokemon essentials then this is the place you're looking for. Essentials is like a base game that you can customize however you want if you want to make a game from scratch. I haven't tried rom hacking so I don't know if it's harder/easier than making a game with pokemon essentials. I'm more familiar with essentials so I can answer questions about that.

The current version of essentials has unlimited tm usage (if that's what you meant), coded up to gen 7 mechanics but has some easily to follow resources to update to gen 8, and more. There is a following pokemon resource for the current version of essentials but don't remember if there is a current plug and play resource for no hms as well for the current version of essentials.

For game mechanics, all of that is very doable either by keeping track of dialogue chosen by increasing a variable, having multiple versions of the same boss, implementing a temporary nuzlocke rule, and game map design.

One big thing you should think about is graphics because based on your description I'd assume you want your game to look a certain way and to do that you'd either need to make custom graphics or find graphics that are close enough to what you want which may be be a challenge. Graphics is something to think about regardless of how you create your game. The story seems interesting enough but think about how these elements would fit in a pokemon world.

Either route needs a program or programs to make a game. Rpg Maker xp is used to make games using pokemon essentials as a base. Rpg maker xp uses the coding language Ruby, which you may need to learn but there are resources online to do so. Regarding rom hacks, I don't know if you need any coding knowledge or just knowledge of how to use the program(s) needed for making the game.

if you're unsure what to use to make your game try watching some tutorials of both and see what you prefer. I know for pokemon essentials, Thundaga has a tutorial series on YT.