A 2-d RTS game (2d games are underrated, broodwar, jump ultimate stars, indie games like Celeste, etc) where you have a mode defending against random disasters like parasprite invasions and other modes to play against the changeling hive or ever-free forest creatures or etc, as different locations in-game. And each pony you recruit is from the city and has different personalities and has some rng involved, so you need to put up fliers that appeal to different ponies to try and recruit them but you need different kinds of ponies or they will all have the same flaws, so you need to come up with creative recruitment solutions to fit their needs. And if the battle migrates to the city ponies naturally panic, so you need to employ a pony with leadership quality then the disaster serves as the event to drum up support. You lose if the city is destroyed or ponies are captured.
It should be campaign style, so losses to the city or ponies being lost can cause future dynamic changes. Or like Lyra gets captured, so Bonbon pledges her support, and stuff like that.
And each pony should have emotions and interests, so their dynamics change. And each has a unique ability, then a race ability. Like all pegasi can fly (except scoots) but then Flutters can also drum up support from animals (really powerful depending on region, but she is shy so equally as hard to get going to support the cause).
And food items should be throwable, and eatable (like pies from that one episode), should be a basic ability everypony has.
And it should be real time strategy not grand strategy.
And a team should gain friendship buffs over time if they stick together mission to mission, so in the campaign you can get all kinds of parties going along, but some dynamics do cause tension between members and might be difficult to overcome.
How ponies are recruited is either the city is simulated, or you buy a poster (temporary upgrade) and ponies rng spawn from a pre-selected set that display an interest in the style of poster based on how appealing to their interest it is. Like if you have a poster that looks mean or tough or scary or militaristic it may appeal to wonderbolts but not Fluttershy. So theres a deck of ponies based on locations and previous events, and its shuffled and draws some cards and if any of the ponies like the poster you got recruits now and can manually control them.
The campaign can be something like 'chaos spread through the land, all the villains n stuff joined forces' So theres different factions based on location but if you lose cities you will have to face combined factions as time goes on, but there are more displaced ponies willing to help the more cities you lose (but that creates economic drain so you have less resources for posters, pies, or other equipment.) And if the population morale goes too low then Windigos also get involved as like a final countdown, if you have any friends or solve the conflict before the windigos fully cause winter then crises averted.
You get game over in campaign from the Windigos or losing all the cities then losing the main invasion against the baddies (if you lose all cities there are all factions present as well).
This would add alot of replay value, and alot of dynamics into the game. You could get alot of challenge runs, like 'bonbon n lyra only' or 'let all the cities get destroyed then win'. And to incentivize that we can actually offer different endings, for no cities destroyed or some or all.
Your ponies in your party level up based on friendship style and level, and can gain more abilities the more types of friendships they have. Like Fluttershy can unlock different bonuses in a party or abilities due to being shy, or due to liking animals. So compatible friends when leveling up can learn animal abilities themselves or protective abilities or moral support thanks to fluttershy.
And I want the game to be winnable with either good control, Or good planning, but a chaos mode (basically hard mode) where you need both to win (and multiple factions can be present in any battle, even if defeated before).
Edit:
And if you don't capture the villains they can support next battle if they escaped. And it costs resources to keep villains captured (but you can make posters to generate resources too) and if the train doesn't get destroyed when the town hall does, ponies evacuate into the next area based on random deck shuffling, but all get captured if the train station gets destroyed in that city. The more captured ponies the more changelings there will be, either attempting infiltration or because of more love draining there are more changelings available as enemy units as time goes on if more get captured.
So like, as the next city lets say gets displaced ponies from the train every 2 minutes, its going to be random cards from the first city a few at a time from the deck of ponies of ponyville who weren't captured, or such. Then if that city is also destroyed except its train, then only those who arrived were added to the city deck (the same deck the posters may recruit from) then now its the edited city deck can send displaced ponies into the next. But the displaced ponies who have determination will auto-support when drawn. And the ponies who have the hopeless tag, can't join even with a relevant poster. Its based on type of disaster and personality type if they get either tag. But if you have the right ponies (leadership) you can change hopelessness into support from refocusing their disgruntlements, so relevant posters make them change to a determined tag even if hopeless, which effects future dynamics.
But changeling infiltrators can try n sow disharmony as well (or if you have very poor attention back at the city while controlling ponies, they can even kidnap ponies that you draw from the deck to apply the poster effects on.)