The only real problem this has it that it doesn’t actually fix an inherent problem with how percentage scaling works, unless you are already thinking about what I’m about to describe.
A 5% speed bonus is hardly noticeable. A speed bonus of 5–20% is slightly noticeable. A speed bonus of 20–50% is pretty good. A speed bonus of 50–75% is really good, but past that, you start falling into the territory of having anyone that decides to make a speed-based build unfun to fight against, because how the heck is anyone supposed to consistently hit a target that’s moving at twice your speed?
It’s the same thing with magic size. At 5–10%, the stat might as well not be there. At 10–80%, the stat would be noticeable, but not too extreme. And past 80%, the person wearing the equipment would probably not even have to aim during fights. Bigger magic can be an interesting upgrade, but not too the point where someone can blow up an entire town with one spell, even with endgame gear. Remember, players at level 1,000 would be able to get the 80% magic size bonus.
My solution to this is setting a limit to how high a certain stat can be. For example, with magic size, you wouldn’t be able to keep boosting your magic size with better gear as you level up. Instead, your gear choices would look something like this at level 100:
- Armor A: +75% magic size
- Armor B: +50% magic size, 75 defense
- Armor C: +25% magic size, 150 defense
- Armor D: 250 defense
And they would look like this at level 500:
- Armor A: +75% magic size
- Armor B: +50% magic size, 500 defense
- Armor C: +25% magic size, 1,200 defense
- Armor D: 2,500 defense
And they would look like this at level 1,000:
- Armor A: +75% magic size
- Armor B: +50% magic size, 4,000 defense
- Armor C: +25% magic size, 10,000 defense
- Armor D: 25,000 defense
And they would look like this at level 30:
- Armor A: +50% magic size
- Armor B: +30% magic size, 15 defense
- Armor C: +15% magic size, 30 defense
- Armor D: 50 defense
This is what I assumed your solution would be:
- Armor A (minimum level: 30): +10% magic size, 30 defense
- Armor B (minimum level: 100): +25% magic size, 400 defense
- Armor C (minimum level: 250): +50% magic size, 1,000 defense
- Armor D (minimum level: 500): +75% magic size, 2,500 defense
- Armor E (minimum level: 750): +100% magic size, 8,000 defense
- Armor F (minimum level: 1,000): +125% magic size, 25,000 defense
As you can see, the early-game playstyle for magic size builds would barely be any different from the playstyle of someone that didn’t bother to invest in magic size, while the endgame playstyle would allow for someone to blow up entire towns way too easily with the 125% magic size bonus.
Now, if you’ve already taken this into account and want a limit on stats like magic size and speed, then I would agree with you entirely. I’m just not sure if that’s the case.