Sample system:
All stats cap at 90,000 or 90% for PVE. All stats on all items are increased to reflect this change. This is persistent everywhere for everyone regardless of level or locale. You can get stats from rating or % boost, either will cap you.
Combined rating and item level still exist and still operate as they currently do in all other aspects.
Stats on items (regardless of item level) are high enough for toons of all levels to reach 50,000+ in all stats if they have fully upgraded gear. Yes, this means a 100 item level ring will have ~5000-10000 stats on it, this is fine.
Combined rating scales with item level still, however, so lower level toons will be stuck below 90,000 and max level toons with high item level gear will slowly drift up to 100,000. Level 10 toons with every single item slot filled in a sensible way might have 40-60k in most important stats, and a level 80 toon with high item level gear will have 80-100k in most important stats, entirely due to the increasing combined rating.
Damage and Max HP still scales with item level in the exact same way.
An additive damage stat is also on weapons (so that higher item level weapons are MUCH better than lower item level weapons so that 400 item level weapons with good equip powers don't overshadow 1200 item level weapons).
When entering scaled content, the scaled locale will have a set damage and Max HP value which is is "characteristic value(CV)". The damage and MaxHP of all toons entering the scaled content are only allowed to be 50% higher or lower than the CV. The dungeon is balanced so that every fight should be in principle doable by a team that is 20% lower than CV, but very hard, a normal challenge for anyone at CV, and progressively easier for parties higher than CV. If you enter the dungeon with 0 damage and 0 MaxHP, you have 50% lower than CV. If you enter the dungeon with 10,000 damage and 2,000,000HP (arbitrary theoretical maximum values(MV) that cannot be exceeded by players), you have 50% higher than CV as your scaled value. Every point of damage and MaxHP from 0-CV that you have will progress you from 0.5CV to CV, and every point of damage and MaxHP from CV to MV will scale your damage and MaxHP in the scaled content from CV to 1.5CV, all linearly.
So if YOUR damage is 5000 and the CV of a dungeon is 1000, then you wind up with 1000 + 222.22 = 1222.22 damage.
If your MaxHP is 500,000 and the CV of the dungeon is 100,000, then you will wind up with 122,222 MaxHP.
In this new system, every toon is shooting uniformly for 90% in every stat they care about either by getting their rating to 90,000 and/or by boosting % to 90 (not this weird, rating til 50% then boost only beyond that).
This is simple, easy to understand, and uniform for everyone.
Every toon ALWAYS gets linearly stronger in all content when their toon gets stronger. With this simple formula it is impossible for a powerful toon to be scaled down to being weaker than a weak toon, but the difference is small in scaled content to make it fair and challenging for all.
This means that improvement is always improvement. Exactly how high those MVs should be set and exactly what the % variance should be are totally arguable. Maybe 50% is too low. Maybe 10,000 damage is too high. Whatever. These can be changed to fit the state of the game.
Toons no longer have to re-balance their stats when they upgrade their item-level due to increasing stat-caps (seriously who came up with this mechanic? This is a *bad* mechanic).
You shouldn't need to worry about rebalancing every source of stats you have because you found a higher item level item. Having your apparent statistical values drop when you upgrade feels bad and is distinctly anti-fun. Upgrades should always be upgrades.
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