It started a few days ago when I "complained" on my status update as how boring is to make weak mobs / low level enemies. Eventually I started to think, why not make all of them interesting? The problem is, well I can't, I mean it won't suit in my current game. But, how about a new game where you fight a boss all time? basically a boss game.
I'm putting here as my personal note as well. When I'm gonna start this one, I don't know.
Story:
It might be the least part I'm gonna think as I don't want to hinder myself because I can't think of narrative. Or maybe no narrative at all. I'm not sure if it's going to turn some people off.
Gameplay:
Section 1: Battle System
The main gameplay would be focusing on battle. And the battle system is not going to use default turn system.
I'm still undecided whether If I want to use Free Turn Battle, Two Rows Battle System, Timeline Order, or Grid Battle System.
Free Turn Battle:
When you're in your turn, you're free to pick any actor and it will instantly action until you run out of char to move.
Pros: It's easier to balance in my opinion
Cons: Agility stat doesn't matter (means you can't really present an agile character).
Two Rows Battle System:
It's a same with FTB, but with row system. When your character on the front/back, it will have different skill. Character on back can be support, while in front switch into offensive mode. So far I'm really satisfied with this approach on my game.
Spoiler
Same pros and cons with FTB I think.
Timeline Order (or ATB if you prefer):
This system is adopted from Child of Light. It has idle phase where you're waiting, and casting phase before you deal damage. During casting phase, if you're being attacked, you gonna get interrupted and back to previous timeline.
Spoiler
Pros: Allow more strategic battle that requires you to pay attention to the surrounding whether you want to attack or defend.
Cons: You can only have two battle members because adding a new actor will make it hectic. Plus, I never have experience on making boss in this kind of system.
Grid Battle System:
Player and enemies are separated in grid. You can make a position as tactical advantage.
Spoiler

Cons: Making it actually balanced and strategic will be quite challenging.
Additionally, an action battle system:
This wasn't my choice as action battle system in RM is kinda wonky. The engine doesn't really support a real time action without slight lag / frameskip from intense processing. Unless if RGD is already perfected, or... I'm going to do this in MV?
Section 2: Player VS Enemy
Party picking:
I started to think this idea with characters selection as party. I've made a lot of original character in the past that went unnoticed because my game concept which featuring those character never been released for many reasons. Basically in this kind of game, where you select few from the character roster, and you gonna try to survive from wave of bosses with those characters.
The pros of doing this is maybe you can submit a cameo from your game to insert as a playable party member here.
The cons is you can't really customize the character since well it's character based.
Boss Waves
Once you have picked the party members, you will be facing a lot of bosses. The idea of this is so that I don't have to worry about having a boss idea that doesn't really fit with my game, ended up wasted. You can also submit your own boss idea.
Every time before boss you are given a certain amount of currency to spend the currency into buying item or something for preparation. You gain some after defeating the boss, so you can choose to save it or use it all together. I'm also planning of "no grinding" in this game (which is ironic as I actually like grinding), all you need to focus is to solve the "puzzle" given by the boss.
Of course I'm also already seeing of "meta characters" will be happening. Basically, use combination of character XYZ is the best. But it's not the point of the game. The point is if you're going to be able to use other combination and still beat the game.
---------------
At least that's it for now. Leave a comment if you have something in mind.