Being skilled

I am tinkering with Heroes By Trade again, trying to work out if skills are being the thing I want them to be.  Right now the basic mechanic is that you roll 1d8, add your Aspect bonus (Strength, Dexterity, Constitution, Intelligence, Willpower, Presence) and then can add an additional bonus if you are trained in the skill being used.

Examples:

I am untrained in Gadgetry and have 5 Dexterity.  I roll 1d8 + 5.

I am trained in Intimidation, and have 5 Presence.  I roll 1d8 + 10.

The system technically allows the GM to swap around what Aspect you use for each skill, but skills are presented with a default Aspect that you would expect to be the right one.  Athletics is Strength, Persuasion is Presence, etc.

Something is digging at my brain though, telling me this isn't quite right.

I am thinking that if the system is going to have flexibility in terms of assigning skills and Aspects to particular rolls, that ought to be front and centre.  You can use Strength + Animals to push a donkey across a bridge, but those two aren't going to pair together much normally, so Animals is paired with Presence and I think pairing them kind of locks people into using them that way.

Ideally I would love to present all skills independent of Aspects, so you would have the GM select an appropriate Skill for the situation, an appropriate Aspect, then you roll and add the two numbers to your roll.

However, this results in adding two different numbers to a roll and that somehow feels clunky.  Instead of the 1d8 + 10 above, it is 1d8 + 5 + 5.  Also sometimes if a different Aspect is chosen it might be 1d8 + 5 + 4, for example.  It feels right to make it a core part of the system that Aspects and skills are chosen independently to best represent the challenge, but it means that people will spend more time figuring out what their bonus is instead of knowing automatically that their favourite thing to do is associated with a fixed number.

It is hard for me to figure out how to value those things.  I like speedy play, so normally I go to great lengths to keep people's bonuses predictable.  I hate play grinding to a halt while players hunt for extra +1 bonuses to beat a challenge.

I have been thinking about ways that I could change the skill mechanics to keep bonuses easy to remember without mucking with them in other ways.  For example, instead of training adding +5 and mastery adding an additional +3, I considered training just adding 1d8 and mastery adding another 1d8.  This would mean that a character who is a master of a skill would be rolling 3d8 and adding their Aspect bonus.  This preserves the nice benefit of only adding one number, but increases randomness a lot.  A 3-24 spread on the 3d8 is enormous, and I have spent enough time complaining about the randomness of a 1-20 die that I am uncomfortable with that.

Then I thought about setting it up so that training granted a 1d8 as above, but mastery simply allowed you to reroll any die you wanted to.  This reduces the max spread, but the spread is still potentially 2-16 instead of 1-8, and that is a lot.  I like the skill system to have a fair bit of predictability so that characters have a sense of what they are likely to be able to accomplish, and so that people who actually stack a lot of bonuses can do amazing things that normal folks cannot.

I suppose I may end up just accepting that skill checks take more time to calculate and set up Training and Mastery as +5/+8 and Aspects separately so people usually need to add two numbers to their roll.  Skill checks are really fast compared to combat resolution anyway so perhaps adding a bit more to it isn't really a bad thing.

Sometimes you have to sacrifice elegance of execution for elegance of presentation in the name of improving the player experience, and this seems like one of those times.