More Early Article Access

I couldn't help myself but write more on this topic. Especially after Jeremy Crawford's stream. Here you go:

Quality of Life Improvements

We received additional insight on the "shove" design changes in the May 15, 2018 Dragon+ stream. It turns out the language of the "shove" mechanic was rewritten for a few reasons:

Rules Loophole. There's a loophole with the shove attack that does not technically require the defender to be conscious. Saving throws are cleaner because the rules are built in.

Reducing References. It's poor form to make a player look up another rule. Just say what it does. This is especially true in the case of an action or attack which also provides an exception to the referenced rule. This might be acceptable if you are providing a small exception to a large ruleset, but not if the exception removes half the ability (in this case, knocking prone).

Speed. The designers opted for a saving throw as opposed to the "shove" contest because it's faster in combat. After playing a few years of 5th Edition D&D, the designers have realized that skill contests are more appropriate for resolution of conflicts outside of combat, whereas combat benefits from having structured single rolls, such as attacks (vs. AC) and spell saves (vs. DC). "Saving throws are faster."

Skill Contests vs. Standard DCs

Specialized race/class features should be stronger than what's generally available to everyone...if they consume the same action economy. If a race/class gets a shove attack feature that takes an attack action, it should do more damage or something tactical.

Another option for building race/class features is to make a regular action/attack a bonus action or reaction. Where should the power level of a race/class feature be when it consumes a different type of action? Should it match the original benchmark? Should it be more powerful, because it's special to the character? Should it be less powerful, to account for the fact that its consuming a different type of action? We can get an idea by examining the design reliance on saving throws:

"[The shove] rule is meant essentially for anybody to be able to use and for nonspecialists. But, you'll notice that most special abilities in the game--whether they are class features in the fighter, or they are spells, or they are monster abilities--when they...clobber somebody and hurl them back, usually its a saving throw."
-- Jeremy Crawford, March 15, 2018 Dungeon+

While a saving throw rule is less variant than a skill contest, it's not necessarily better for the attacker. A standard DC (8 + Proficiency + Strength) is easier to beat than a proficient Athletics roll (10.5 + Proficiency + Strength) on average. You are taking a risk by rolling dice, but the odds are 65% that you'll roll at least an 8:

On the other hand, the saving throw rule may nerf the defender's save chance, since they lose the chance to choose the better of their Strength or Dexterity check from the shove contest. This will depend on whether the defender has Strength save proficiency, Athletics (Strength) proficiency, or Acrobatics (Dexterity) proficiency.

In order for the saving throw rule to benefit the attacker, the defender must exceed the average 2.5 DC difference. The defender's Dexterity save needs to be 3 higher than the better of their Athletics (Strength) or Acrobatics (Dexterity) skill. Here's the factors at play:

Strength vs Dexterity. In general, most monsters have higher Strength saves than Dexterity saves, so the change does not harm them. The majority whose Dexterity so far outstrips their Strength (5+) are small beasts that serve as familiars (30+), fodder minions (Goblin, Kobold, Quasit, Imp), incorporeal creatures that don't care if they are pushed (Banshee, Shadow Demon, Air Elemental), or tiny undead that don't care because they float (Demilich, Flameskull, Will-O'-Wisp).

Skill Proficiencies. A saving throw rule is more likely to harm creatures that can no longer add their Athletics (Strength) or Acrobatics (Dexterity) proficiencies in a shove contest. This is a very small subset of the baddies you may encounter. Among all the creatures in the Basic Rules, Monster Manual, and Volo's Guide to Monsters (including veterans and skins), only 32 have proficiency in Athletics (Strength) and 10 in Acrobatics (Dexterity). Whereas 24 have Strength save proficiency.

Let's look deeper. Creatures with Strength save proficiency are popular: most Fiends, Undead, Gith, couple Giants. Athletics proficiency goes to Giants, Grung, a few monkeys, and the notorious Redcap. The Fey creatures Darkling and Quickling are the only non-veteran creatures with Acrobatics skill. Since Strength save proficiency is less numerous, but arguably more ubiquitous, there is little counteracting effect. Unless you're playing a campaign full of Giants (i.e. Storm King's Thunder), a saving throw rule is probably worse than a skill contest. 

So there you have it. In order to balance a regular action that you have converted to a reaction or bonus action for a class ability, you may want to consider dampening the effect. Also consider the other options available to your race/class (such as Hammering Horns' deference to Goring Rush). If you are building a race, be sensitive to the fact that the player's class selection may give them access to Bonus Actions that can crowd that design space.