So here are some ideas. Just rough drafts. I find it easier to analyze things when I see it presented in a more formal format. B&B originally had backgrounds, and after thinking about it and thinking about what you said, I think for a primer the more familiarity the better. So I stripped out those custom options from the species and put a background list back in.
I appreciate you giving my feedback consideration, but I see you are still adding new things.
Why add these traits to humans if they aren't part of 5E at all?
The Orc would be perfect if you went with Half-Orc (or I guess it is just Orc in 2024), removed the Armor Master trait and gave them proficiency in Intimidation maybe, especially considering the fluff text .
If we look at the half-orc (2014) it has: Darkvision, Menacing, Relentless Endurance, Savage Attacks.
The 2024 Orc removes Menacing and Savage Attacks for Adrenaline Rush.
The two common traits are Darkvision and Relentless Endurance, so I would introduce Orc (or Half-Orc) in a primer with those two features.
I would focus on simplifying each race to two (no more than three) key traits:
- Dragonborn: Breath Weapon and Damage Resistance, third maybe Darkvision
- Dwarf: Dwarven Resilience and Tool Proficiency (any artisan tool or offer a better selection IMO), third maybe Dwarven Combat Training
- Elf: Keen Senses and Fey Ancestry; third maybe Trance but I see this get abused too often
- Gnome: Darkvision and Gnome Cunning, third no idea...
- Halfling: Lucky and Halfling Nimbleness (if you use small size is different from medium), or Brave (if you treat small = medium); or Brave as the third trait
- Half-Elf: Fey Ancestry and Skill Versatility, third no clue, but certainly not Darkvision!
- Half-Orc: Darkvision and Relentless Endurance, third Menacing for Intimidation proficiency
- Human: a skill and (since you wouldn't want feat) Heroic (the Resourceful from 2024). Alternatively, I would give them Prodigy baked in so in total: two skills, a tool, a language; or treat Prodigy as the third trait
- Tiefling: Darkvision and Hellish Resistance, third Infernal Legacy
For most of these, giving a third trait is pretty much the RAW 5E race for 2014, so I would really try to limit it to two or auto-select the subrace to grant the third trait if needed--particularly if you could avoid Darkvision.
Anyway, for your Tiefling, Devilish Heritage offers the same benefit as Jack-of-All-Trades for your Humans... so they do the same thing? Also, as a primer for 5E I would not use a name for a trait that is also a feature name (Bard's JoAT).
Resistance is fine but why offer the choice if this is a primer? It lends itself too much like a subrace option and is neither offered in 5E or 5E 2024.
Now, if you want to step away from the primer concept more, that's your choice since it is your project. But at that point I just start seeing this as a simplified B&B v2 or something.
There are tons of game systems out there that are akin to 5E, using the sacred-six ability scores, Hit Dice, classes, levels, etc. even if they deviate from 5E quite a bit. Some of those a pretty simple and work well as an intro to "D&D-based" RPGs, but none of them are a
true 5E basic or primer IMO because they deviate--adding new traits or features, new classes, new spells, etc. Others alter things to create a different "feel", like lowering Hit Dice or such, changes which IMO (at this point--I've been SO guilty of this myself!!!) really make little actual difference in the game.
I understand the logic and inspiration behind the stuff you've done, but to me it is a step away from what I thought you were trying to do (whether you want this to serve for 2014 or 2024...).
So, all in all just let me know if you are moving more away from my concept of a primer or if you want me to keep trying to pull you back towards it.
If you don't want to create something more like what I am looking for, no worries, and I'll still offer feedback of course!