That's a lot of numbers, but the take-away I'm getting from this is that, in order to play an average character - the type of character who won't immediately die - everyone should have at least 14 in Constitution.
That can't be right.
I agree in two directions.
First: Constitution makes almost no difference unless it is negative or maxed.
Second: The contribution brought to survival by Constitution is cumulative. At level one, it's pretty meaningless.
Even a Barbarian Dwarf or a Variant Human Barbarian with Toughness and maximum Constitution is only going to have 19HP (1d12+5Con+2 toughness). That's a lot, but not enough to really secure a character against a few good hits. They're still very killable.
Most characters will be sitting somewhere in the 8-12 range of health, except for maybe that one really scrawny Wizard who has 6HP. Adding one or two hit points to any of those numbers, while it
looks like a lot, is ostensibly meaningless. 5E has by far, the
weakest purpose of Con that I've ever seen. It could be completely removed and it's appropriate checks assigned to almost any other score and noone would notice the difference.
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At the topic on hand, this system is overlycomplex and promotes mediocrity. If you want a "simple" system that achieves the same goals, just create a "flat" array like: 16, 15, 15, 14, 14, 13. Or go even simpler and give every score a 14 (or whatever number you pull out of your ear).
I like the idea of classes giving stat bumps, but I'd turn the idea around like this: Remove the "base" +2 stat bump that each race gets, leaving only the "subrace specific" bump and then give each class a floating +X(1 or 2, whatever works for your game) to one of two of their scores (in the case of races with no subrace, just remove the +2 bump). Boom. You will immediately see a lot less elf rogues and a lot more dragonborn wizards. Or whatever else people can get creative with because the +1 is far less determination of what class you're going to be playing.
For added clarity, here's a list:
Hill Dwarf: +1 Wis
Mountain Dwarf: +2 Str
--Dwarves previously got +2 Con at base
High Elf: +1 Int
Wood Elf: +1 Wis
Dark Elf(Drow): +Cha
Eladrin(DMG): +1 Wis
--Elves previously got +2 Dex at base
Lightfoot: +1 Cha
Stout: +1 Con
--Halflings previously got +2 Dex at base
Humans (as is)
-Why? Because there's no need. Humans have no racial traits, which puts the stock human below the other races. Variant human puts them on-par with other races.
Dragonborn: +1 Cha
--Previously had +2 Str
Rock: +1 Con
Forest: +1 Dex
--Gnomes previously got +2 Int at base
Half Elf: +1 to any two scores
--Previously had +2 Cha as well
Half Orc: +1 Con
--previously had +2 Str as well
Tiefling: +1 Int
--previously had +2 Cha
All the classes would then offer a +1 in either of their "primary scores". Barbarians are strong because they're trained to be strong, not because all the strong races become barbarians.
Done and done.
Personally: I'd go a little further and give each race a floating +1 in either of their possible scores. So, Tieflings could get +1 in Int or +1 to Cha, High Elves could get +1 to Dex or +1 to Int, etc... I think I'll save this for the next game I run.