I want to know, for example, what it means if my sword has a damage of "70-177" and what that means for the "attacking value" of my warrior.
I honestly don't understand what you find so confusing about this.
Your damage value is listed in the stats screen, so if your damage is listed as "70-177", that means that you will do somewhere between 70 and 177 damage with an attack, before armour and resistances of the target are taken into account.
What are the armour and resistances of the target? Put points into Loremaster to find out (once it isn't bugged, that is). Points into Loremaster will also let you know how much health the enemy has so you can decide if targeting it is a good use of your time.
What is an "attacking value"?
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I agree that casting times for high-level spells could be interesting and something that D:OS could make use of, as well as giving Willpower something else to do, since so far, mental statuses seem very rare.
I don't think under such a system, once a spell is charged it should automatically cast, though. The battlefield can have changed quite a bit in the turns since. You should have the choice whether to cast it or not, heck, maybe even you can hold off on using it until later in the fight, since you did spend those turns charging it up.
I don't think that being able to walk around in real-time means that you can't use spells which take multiple turns to charge. One round is 6 seconds of real time, so when casting the spell in real time, your character freezes and a little progress bar appears overhead like with crafting or identifying to show your progress until the spell is charged and ready.
My water/air mage instead could use his lightning spell every turn.
You are mistaken. Blitzbolt has a 2 turn cooldown, so you can only use it every other turn. You can't use it every turn. It also has only a 35% chance to stun (I believe higher if the enemy is wet).
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I also don't really agree with your wish for magic. You want mages, in addition to their existing wide variety of damage, AoE, status-inflicting, heals, buffs, debuffs, summons, and control spells, to also get high-damage single-target spells, and you want them to be able to cast an important spell every single turn. A "button you press to make something awesome happen", as it were.
You essentially want D:OS to follow the unbalanced "Linear Warriors, Quadratic Wizards" formula, and be able to do everything with ease.
Sorry, but I can't agree that would be the right direction to take D:OS.
So, I don't have a problem with the "extreme" positions you can currently choose in decision dialogues : I care that whatever my choice is, it will affect the game in a (relatively speaking) meaningful, tangible way. I'll always prefer limited, meaningful choices, than multiple, purely cosmetic options.
If there were multiple different dialogue options, then they WOULDN'T be cosmetic, it would be easy to adjust the numbers they move the affection stat behind the scenes for each of the options, so that each option would give a different amount of positive or negative affection.
It's the actual writing of all those dialogue options that would be the hard part.