Faolyn
(she/her)
OK, this one is very heavily write-in.
Background skills and Class skills: Lanefan suggested the following:
The first is as above. Your background and class give you specific skills. If you take the Courtier background, you know Politics or Knowledge: Nobility or something like that. If you take the Acolyte background, you know Religious Ritual. Likewise, if you're a Rogue, you know Pickpocketing and Hide in Shadows. If you're a Fighter, you know Knowledge: Weapons and Armor or History (War). The pros, as I see it, would be a lot of niche protection (you'd never have another occasion where the rogue or bard is better at Arcana or Religion than the wizard or cleric is, because of expertise), and it would lend itself to more individualized characters because each background/class combo would be far more unique. The cons is that the skill list would get hella long and would never really be complete.
Or, they give you open-ended skills. If you take the Courtier background, you know the Courtier skill or are a Fighter, and you can roll for those skills whenever they would be useful (DM's discretion), without the need to break it down into individual skill trees. The pros are the same as above. The con is that it's open to a lot more player and DM interpretation and, potentially, "mother may I?"-ing. Some of this could be alleviated if, in each background and class, you actually list what the skills are used for. Even in generic terms, it's useful.
You could also include Culture skills this way. If you take the Cosmopolitan background (to steal one from Level Up), then you could either have several skills for that culture (say, Area Knowledge, Local History, Schmoozing, etc.) or, once again, just have Cosmopolitan as a skill.
Attribute skills: Another thought I had is to remove the skill list and simply roll your stat when needed. Need to remember something? Roll Intelligence. Need to read somebody's emotions or to find out if they're lying? Roll Wisdom. Need to be sneaky? Roll Dex. Each attribute would have a list of things that it covers, to help determine what to roll.
Skill Specializations: Level Up lets you take skill specializations within each skill. With Arcana, you can specialize in Forbidden Knowledge, The Planes, Ooze Lore, etc. With Deception, you can specialize in Concealing Emotions or Mimicry, etc.
I can see doing this both with individual skills and with background/class/culture/attribute skills. The pros would be that you could have the background/class/culture/attribute skills and still allow for individualization and for PCs to not be equally good at everything.
Expertise/Skill Bonuses: This could be done as per 5e (double your proficiency bonus), as per Level Up (add a d4 expertise die, which can increase to a d6 and then a d8), or as a flat +2 per level of bonus. It really depends on how much math you want to include.
EDIT: When I wrote "+2 per level" for Expertise (second to last option), I did not mean class level. I meant more like level of bonus. So you could start out with a +2 but could get even more expertise later on and raise that to +4.
Background skills and Class skills: Lanefan suggested the following:
The way I see it, if these are used, there are two options."Life skills" - these are the things you may or may not have happened to learn while growing up, or in some cases represent talents you were simply born with. Random roll for how good you are at each, no modifiers for class, occasional modifiers for species. Everyone has to roll for the first three, any others are purely at the player's option unless it somehow becomes relevant during play.
Swimming
Boating
Riding
Singing (optional)
Drawing (optional)
Etc. (optional)
Class-specific skills - skills certain classes need in order to do their jobs. This covers Thieving skills, Rangering skills, and so on, and would be bespoke to each class that needs them.
The first is as above. Your background and class give you specific skills. If you take the Courtier background, you know Politics or Knowledge: Nobility or something like that. If you take the Acolyte background, you know Religious Ritual. Likewise, if you're a Rogue, you know Pickpocketing and Hide in Shadows. If you're a Fighter, you know Knowledge: Weapons and Armor or History (War). The pros, as I see it, would be a lot of niche protection (you'd never have another occasion where the rogue or bard is better at Arcana or Religion than the wizard or cleric is, because of expertise), and it would lend itself to more individualized characters because each background/class combo would be far more unique. The cons is that the skill list would get hella long and would never really be complete.
Or, they give you open-ended skills. If you take the Courtier background, you know the Courtier skill or are a Fighter, and you can roll for those skills whenever they would be useful (DM's discretion), without the need to break it down into individual skill trees. The pros are the same as above. The con is that it's open to a lot more player and DM interpretation and, potentially, "mother may I?"-ing. Some of this could be alleviated if, in each background and class, you actually list what the skills are used for. Even in generic terms, it's useful.
You could also include Culture skills this way. If you take the Cosmopolitan background (to steal one from Level Up), then you could either have several skills for that culture (say, Area Knowledge, Local History, Schmoozing, etc.) or, once again, just have Cosmopolitan as a skill.
Attribute skills: Another thought I had is to remove the skill list and simply roll your stat when needed. Need to remember something? Roll Intelligence. Need to read somebody's emotions or to find out if they're lying? Roll Wisdom. Need to be sneaky? Roll Dex. Each attribute would have a list of things that it covers, to help determine what to roll.
Skill Specializations: Level Up lets you take skill specializations within each skill. With Arcana, you can specialize in Forbidden Knowledge, The Planes, Ooze Lore, etc. With Deception, you can specialize in Concealing Emotions or Mimicry, etc.
I can see doing this both with individual skills and with background/class/culture/attribute skills. The pros would be that you could have the background/class/culture/attribute skills and still allow for individualization and for PCs to not be equally good at everything.
Expertise/Skill Bonuses: This could be done as per 5e (double your proficiency bonus), as per Level Up (add a d4 expertise die, which can increase to a d6 and then a d8), or as a flat +2 per level of bonus. It really depends on how much math you want to include.
EDIT: When I wrote "+2 per level" for Expertise (second to last option), I did not mean class level. I meant more like level of bonus. So you could start out with a +2 but could get even more expertise later on and raise that to +4.