OK, but that has nothing to do with allowing people to assign their +2/+1 as they wish.
I beg to differ.
1: There's a max cap on attributes in 5e anyway, which means that even if all goliaths started out with +2 in Strength and no halflings did, they could still both end up with 20 Str anyway. Just not at the same time.
And I would've gone the other way. I would have set the cap at 20+racial modifier.
And even as it is. it does affect first level. I've no problem with high level PCs getting higher stats, because every high level PC is going to get access to amazing abilities. But they have to earn it. They shouldn't be able to just claim to be stronger than a goliath at 1st level, any more than they should be able to choose to be the best fighter or best wizard in the world at 1st level. ALL these things should be earned by levelling up.
2: Strength, the ability score, is not a direct comparison to strength, the effect caused by muscles. It's an abstract ability to determine how much extra damage they do with weapons. Also, Small creatures can't use heavy weapons without a hefty penalty, which means they're limited in the amount of damage they can do anyway.
According to the PHB p175: "Strength measures bodily power, athletic training, and the extent to which you can exert raw physical force." So, a.) it is NOT
just the extra damage they do with weapons, and b.) having high Dex (which halflings have) affects damage just as much as Str.
2a: In the real world, many small creatures are actually proportionately stronger than larger ones. I've read that a mouse can lift up to twice its body weight and can easily support its weight with one paw, while an elephant can't. Mice can also jump and climb--both functions of Strength in D&D--while elephants can't.
In the game Stormbringer (1980), and the Chaosium rules upon which they were based (RuneQuest), the Strength attribute described the
proportional strength, and was combined with the Size attribute to see how much extra damage a creature dealt.
But that is definitely NOT the case with D&D 5e, or with any version of D&D.
We can test this! Let's go to the 5e Monster Manual and look up the entries for Elephant and Rat (since mice don't have an entry). If Str is absolute in 5e, elephants will be stronger than rats. But if Str is relative in 5e, rats will be stronger than elephants.
Let's have a look:-
Elephant (p322): Str 22
Rat (p335): Str 2
Conclusion: in D&D, strength is absolute, NOT proportionate.
3: Goliaths (and firbolgs, bugbears, orcs, loxodon, and centaurs) are always going to be naturally stronger than halflings (and gnomes, goblins, and kobolds) because goliaths can lift and carry things like Large creatures and Small creatures get a penalty to lifting and carrying things. So even if a halfling has a higher Strength than a goliath, it still won't be able to out-lift a goliath. And most people in the real world consider lifting capacity to be a better indication of innate physical strength than the ability to hit people, which is seen as a learned skill.
3a: Lots of tables barely even care about encumbrance or lifting abilities anyway, except at those in-game times when they have to lift a gate or bend a bar. And that's an Athletics roll, which is a skill that all goliaths have.
As mentioned above, in D&D the Strength ability score is a combination of several things, and lifting power is but one of them. Yes, there are ways to increase that aspect individually (like the Powerful Build trait), just like there are ways to increase athletic training individually (the Athletics skill, the Athlete feat). But they ALL are
modifiers to their
actual Strength score.
4: These rules apply only to PCs, of which there are usually no more than 4-6 in any given world. Assuming that any of those PCs actually are halflings (when there are so many races to choose from), then having one halfling be a muscle-bound steroid user among the tens of thousands, hundreds of thousands, or even millions of halflings in that world isn't going to hurt anything--nor will that one 198-pound goliath weakling.
I do not see the Race modifications to only apply to the six PCs in the world! I think that is disingenuous. Those game mechanics apply to all members of that race, unless further rules say otherwise.
When we want to know what a race is like compared to humans, we look at what the racial modifiers are in addition to their traits.
And if you want to be a weak example of a goliath or a strong example of a halfling, we simulate that by applying our six rolled (or assigned or bought) scores to whatever abilities we want. So putting your 18 (or 15, whichever is your best) in Strength really does make you a steroid-using halfling, stronger than the
average goliath (12.5) and in a great position to get even stronger
with experience, which is how the game works!
5: Assuming a player even wants to be a a super-strong halfling, of course. Like the game-breaking influx of mountain dwarf wizards that never happened, there aren't likely to be that many players who desperately want to play a super-strong halfling. But there are going to be a few, so is it really that big a deal to let them?
6:. A bucolic halfling rarely has to carry a lot of heavy things at all, besides the occasional keg of ale or particularly large wheel of cheese. A halfling raised in a more strength-based society would develop a more muscular frame than one who wasn't. Likewise, a goliath raised in a culture that didn't require a lot of physical activity would be much more physically weak than one raised in a "traditional" goliath culture.
Which is why you can assign a big score to Strength if you want. But at least the strongest 1st level goliath will be stronger than the strongest 1st level halfling, and the world still makes sense!
A few days ago I posted that our new campaign will have a houserule that any race with a +2 racial modifier to any particular ability score may, at character creation, swap that +2 for any feat for which they qualify, unless that race already gives floating bonuses to ability scores. The upshot is that every single race can have that essential(!) +3 modifier to their prime stat at level 1 (if they choose the right half feat). It also widens the availability of feats at 1st level, while still leaving the set bonuses for the race as a whole so the world still makes sense.
I said I'd share the results of this houserule on the character creation of our group.
I had already developed a character idea as a variant human, and this new rule did not tempt me to change that concept.
Out of the other five players, one chose a variant human, one chose a non-variant human, one chose a half-elf (so the new rule had no effect on them), one chose a variant tiefling from Mordenkainen's (Glasya) but since they are also a sorcerer they chose to keep their racial +2 to Charisma, and the last is playing a dragonborn fighter and chose to keep their racial +2 Strength.
In the end, no-one took advantage of this houserule.