Since you seem to be working on a major version currently, I thought this was a good time.
About Saves
Currently, saves do almost nothing. Even the save type your character is theoretically good at (i.e. the one depending on your main stat and likely supported by a few haphazard item and skill buffs) rarely do anything. If an enemy attacks you with an ability, it will hit almost all the time (unless you have some hard miss chance) and for 100% effect length.
I think I can count on one hand the number of times an effect missed me or was reduced in severity because of saves in my last two playthroughs (which were both normal wins with about 5 deaths each, btw - almost all of those by cc spirals).
This (together with the imho overall slightly too harsh diminishing returns of secondary stat stacking) makes any investment into saves (and by extension, attributes) feel very bad and not worth the effort and leads to the % immunity vs status effects stats to be overly valued, to the point that one routinely dismisses tier 5 items because the tier 1 item with 35% stun and disarm immunity is just so much better, for example.
I suggest having a look at the scaling of all secondary stats. Maybe lighten up a bit by making 4 tiers of 25 each instead of 5 of 20 each, or make the tier breakpoints nonlinear like 10/30/60/100/150 or something to that effect. Additionally, the effect time reduction on cc should trigger more often and with relevant numbers. Both these changes combined would go a long way to make investing in direct saves via items/skills or indirectly via attribute points feel meaningful for mid-level investments and not a waste of points for your primary stats.
At the same time, this would indirectly reduce the value of cc immunity stats on items, which makes for an overall more interesting decision making progress (right now, the main stats everyone looks for are these, life and sometimes crit, with everything else being an afterthought).
CC chains
One thing many, many rpg-like games have in common is that they use the same spells for players as for the enemies. That is a fluffy and on first glance reasonable stance, but it breaks the moment you think about hard cc and the fact that there is only one player but bazillions of foes that tend to not fight fair 1v1s
TOME has that problem and tries to solve it by giving out said immunities and spells to get rid of such effects. This usually works fine, but it always breaks down with the heavy cc mobs or the rooms of doom where 2-3 cc using enemies are engaging you at the same time. Most character deaths after a certain level are "could not have done much else" deaths where you walk down a stair or open a door, get chain-cced and die, and an even bigger percentage of "almost deaths" are because of these situations but abusing the stairs.I actually like that you have to be prepared for cc. It gives wild infusions and similarly working talents a place and makes for interesting gameplay. The problem is that in said situations, the gameplay gets very binary, very fast. Either you have accumulated immunities against almost all cc types or you do not, and even then, one opening might kill you because there are just so many silences or pinnings or whatever flying around that your 1-2 countermeasures cannot hold up, cooldown-wise.
The above suggestion about making sure cc duration reduction via saves triggers more often would help out a bit in these situations, as would the following suggested rule:
CC effects of the same type have diminishing returns when used on the same target within a certain time frame. Either future applications have more and more reduced durations or you gain a short immunity window after one effect ends.
Example variant 1) You get silenced by a rare mob for 5 turns (8 reduced by 3 because saves matter). The mobs silence spell has a cooldown of 6 turns. After the silence wears off, you are free for one turn, then the mob hits you again. But this time, it gets diminishing returns because it is hitting you again with the same type of cc within a short timeframe. Instead of the silence being similarly powerful again, it, say, works half as long base (so 4 reduced by 2-3 because saves matter).
Example variant 2) You get bombared by almost every single cc effect there is after walking down a stair and doing one action. You decide to cleanse the freeze with your physical wild infusion and are now free to act at least once. Instead of running up the stairs scratching your head on how to actually progress here, you now know that you will be immune to stuns/freezes for, say, 3 turns. Because of this, you actually stay to play the game because you have a chance if you use the right talents in the right order.
Some enemies simply have too many cc types at once
This ties into the above heavily, but since most cleanses only remove 1 cc effect from you and so many spells you get hit with apply multiple types, it gets frustrating very quickly. This gets even more problematic due to the fact that you cannot control which effect gets removed. Usually the game will chose the "correct", i.e. worst one, but not always.
Either reducing the amount of multi-cc enemies and/or giving players more multi-remove abilities would help making these situations feel less arbitrary.
Foes have feel... err saves, too
Both of these themes also apply to all our enemies, so completely locking down powerful bosses is now much harder to accomplish than before. Again, this makes the game less binary. Instead of either cheesing or getting cheesed, both sides now have a fighting chance.
If these changes make the game to easy overall, buffing some enemy types or their level scaling or whatnot is easily done, but the gameplay now rests on a less binary and more involving basis. More decision-driven successes and failures are good.
