I looked through the Japanese wiki and it turns out they actually found out the stat formulas and other technical details, so here they are for anyone who wants them or wants to add them to the wiki.
Base ValuesHP Base = (Lv+6)*Growth Rate + 10
ATK/MAG/DEF/MND Base = (Lv+4)* Growth Rate + 4
SPD Base = (Lv+10)*(Growth Rate/32)
Growth RatesFinal Growth Rate = Base Character Growth Rate + Subclass Boost + Gem Boost + Skill Boost
Subclass Boost = Varies (See Below Table)
Gem Boost = 0.2 (1 if MP or TP) * Number of Gems Used
HP Skill Boost = 0.4 (1.2 if High Boost) * Skill Lv.
ATK/MAG Skill Boost = 0.2 (1.0 if High Boost) * Skill Lv.
DEF/MND Skill Boost = 0.2 0.8 if High Boost) * Skill Lv.
SPD Skill Boost = 0.14 (0.6 if High Boost) * Skill Lv.
Final ValuesFinal Value = floor(floor(Base Value)*Multiplier)
SPD Final Value = floor(floor(Base Value)*Multiplier)+100
Multiplier = 1 + Equipment Bonus + Lv. Bonus * 0.04 + Stat Lv. * 0.02
Subclass Growth Rate Boosts | HP | ATK | MAG | DEF | MND | SPD | MP | TP |
Guardian | 0.8 | - | - | 0.4 | 0.4 | - | - | 4 |
Monk | - | - | - | - | - | 0.6 | - | 6 |
Warrior | 0.6 | 0.4 | - | 0.4 | - | - | - | 4 |
Sorcerer | - | - | 0.4 | - | 0.4 | - | 2 | 2 |
Healer | - | - | - | - | 0.4 | - | 2 | - |
Enhancer | - | - | - | - | 0.4 | - | 2 | - |
Hexer | - | - | - | - | - | 0.4 | 3 | 3 |
Toxicologist | 0.4 | - | - | - | - | - | 2 | 4 |
Magician | - | - | - | - | 0.4 | 0.2 | 6 | - |
Pharmacologist | 0.8 | - | - | - | 0.4 | - | 2 | 4 |
Strategist | - | - | - | 0.4 | 0.4 | - | 2 | 4 |
Gambler | - | 0.4 | 0.4 | - | - | - | - | - |
Diva | 0.4 | - | - | - | - | 1.0 | - | 4 |
Transcendent | 0.3 | 0.3 | 0.3 | 0.3 | 0.3 | 0.3 | - | - |
I apologize if the table is a little messy.