So, what should the attribute numbers look like, in the sequel?
I've been working from the assumption that the ceiling would be +3, but the paradigm has shifted so many times, it's probably worth reexamining. In a previous post, we've established that the baseline hit chance for weapon attacks is expected to be 72.42% -- so with a two-handed attack adding double STR (+3 * 2 = +6) mod, the [lowest 1 of 3d6] roll (2.04) computed through the hit chance produces a 5.822568 DPR result. Now, if we take the same roll and hit chance values but use only a +2 mod, we get 2.925768 -- which when doubled results in 5.851536, representing a two-weapon fighting routine. This is a great starting point, as these values are very close to one another.
So if the desire is to get the "TWF stat" to always be a +2, it probably stands to reason that it should be something like "lower of STR or DEX" allowing those stats to be either +3/+2 or +2/+2. The other way to do it might be "middle of STR/DEX/AGIL" which also has implications for spellcasting.
If the idea is to balance 3 stats against one another, that likely indicates that the idea is to make the lowest stat a +1, rather than a +2/+2/+3 array. This would be necessary for spellcasting, if the idea is that the "cantrip stat" should always be a +1, for example. This means that the overall array would consist of a single +3, a single +2, and then +1s for the remaining four attributes -- because this assumes 3 spellcasting attributes, and thus 6 attributes in total. We've mentioned before that maybe having +2 be the "minimum" spellcasting stat could be an acceptable quirk of the system, if the alternative is to crowbar in an entire 6th attribute.
Should we complicate the matter by having separate pools of attribute points for physical stats and for spellcasting stats? This actually seems like it would work better for producing the desired results, while allowing for more than just a single +3 and/or +2 stat. Something like a floating +1 based on class/subclass would be a mechanic that works well, for this conceit. If we go with these ideas, it seems like you'd have 3 points to split between 2 spellcasting stats, and 5 points to split between 3 physical stats -- in addition to that floating +1.
If spellcasting is to function off of the lower/higher of two mental stats, the class bonus would help to differentiate builds a little bit, i.e. if a Sorcerer is assumed to get a +1 CHA while a Wizard gets a +1 INT. Similarly, if a Paladin's "dice pool stat" is CHA, they might get a bonus to that stat, requiring them to focus their physical stats more on one mode of combat; by contrast, a Fighter might get a boost to STR or DEX, allowing them to be equally at home with two-handed weapons or TWF.
Is there room for a +0 stat, in the array? Well, if there is, it seems like it would only fit into the physical stat side of things (regardless of how many mental stats there ends up being.) Much like how attributes contribute to skills in TNP, it might be easiest to assume that everything starts at "rank 1" and then increases from there. So far, I haven't come across anything to suggest that the cap needs to be higher than +3...
Really, the question then becomes whether the dice pools will consist of 1 stat or 2; some of the earliest theorycrafting for "d6 pool" suggested a normal melee attack would add +STR number of dice to the pool, and a Paladin's Smite ability would also add +CHA number of dice to the pool. With the designs migrating to "2d6 + pool" I feel like the necessity for double-stat pools has gone away. Worth mentioning here, I've also floated the idea that "daily" powers might allow all dice in the pool to contribute towards damage; this means you could put your highest 2 dice towards the attack roll (ensuring the best chance of hitting) without missing out on those dice, for their damage potential. This is something that harkens back to the "class dice bonuses" in TNP, most of which can be used for attack or damage, but some of which can also be used for both.
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I should have a bit more free time coming up later in the month, so expect the next post to be out by October 21st at the latest. A third post will also be out before the end of this month.