Well to be fair the growth system in Three Houses isn't too different from the old games, the only thing that's different is how class advance works.
In the old games if you entered a certain class, you would be stuck to the class tree. So Myrmidons would always become Swordmasters, or Archers always became Snipers.
It shook up a bit in Fates/Awakening, when anyone can reclass to something else. Although limited. Like Lucina can turn into a Pegasus Knight and reap all the benefits that come with it, for example.
In Three Houses, everyone can become anything they like, honestly it's more or less the Echoes system. However in Three Houses, in order to become something, you needed to be proficient enough in the related skills. For example to become an Archer you needed to have a certain rank in Bow, and to become an Armored Knight, you needed a certain level of skill in Heavy Armor and Axe.
In this RP we can start off at any basic class, but as the RP goes on you will get chances to divert into new professions.
Although weapon skill will actually work a bit differently here. Instead you will be picking your Talents (ie. Sword, Axe, Bow, White or Black magic).
Whatever Talents you possess will affect what classes you will have access to, should you be given the chance to change class, or advance class.
The system is almost done, but for the RP's sake I've made it my aim to streamline the growth process while giving options. Moreover since the RP does run on limited chapters, you may want to think about what you want to end up being as well.
I'll link it in this thread soon as that's done. After which I can focus on fleshing out the nations that are directly involved with the RP.
Renose,
xVampire3go,
adncod,
yoshua171,
EnterTheHero,
Ikan,
Bacon