Well, as you called out in your first post, rogues and bards (and PCs with the skill expert feat) can get expertise, which makes the skill check math substantially more favorable to a PC than a save or attack roll. After that, you can have a friend cast the 2nd level spell Enhance Ability (Bull's Strength), or cast it yourself, to get advantage on strength checks. That simple combo gets better and better, relative to monsters, as a PC gains levels, since proficiency bonus scales and monsters, generally, get only marginally better at athletics checks due to strength increases (dex tends to be lower than str). Another 2nd level spell Enlarge/Reduce, helps substantially with the size restrictions. Those are most of the tools you need to grapple reliably (for more thorough info, see
treantmonk's vid on it).
It's easy, with just a little set up, and without sacrificing very much in other areas, to build a PC that can pretty reliably, for example, grab an iron golem, shove it on its face (so it has disadvantage on
all attacks), and give it nuggies while the rest of the party beats on it with advantage on their attacks (from prone).
The new rules have a DC that is
only as good as a caster, but the current rules' contested roll is potentially much harder for a monster to beat than caster DC.
Unless you're a monk, you have to decide before the attack hits that you're going to make an unarmed strike--which is probably not what you were going to do otherwise.
Shove uses "one of your attacks" just like grapple does.
But ya, the PC needs to be built to have two attacks, expertise in athletics, and, ideally, a source of advantage, to get the most out of grappling. A player that doesn't know the full combo running a PC that isn't built to do grapples isn't going to find them useful. And it isn't intuitive how to set up for the combo or why it's good--since most players haven't read all the monster statblocks and learned that most of them suck at skill checks, and most player's don't immediately grok that bards are gonna be better at wrestling than barbarians.
Grapples are a rule that rewards system mastery. I therefore understand why this change is being made--but I don't particularly like the changes because they make it harder to use grappling in a fun and high impact way.
A decently strong combo, that can be used at will, and that synergizes massively with battlefield control (i.e. cheese grater that troll back and forth across the spike growth for fun and profit) might be getting replaced with a 'give an enemy disadvantage on attacks against targets other than you' effect. It's not terrible, but it needs more cowbell.
That's a good point. If they make the grappler feat strong and/or interesting, I might change my mind about the new rules--something like an option to grapple after hitting with a normal weapon attack
or enemies save against your grapples with disadvantage.
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I strongly agree with the bolded (emphasis mine) line of your post. It is the main issue. There need to be a robust set of player options that make save DCs against grappling harder. Admittedly, there are also a ton of features which impose disadvantage (or other modifications) on saves, but they are
always more limited since they work with spells; there's no class feature that lets you double the proficiency bonus in your spell DC calculation.
But, that said, I don't hate the new rules. They make grapples work more like the game's other features do (like
spells, for better or worse). And they are more intuitive; the 20 str bruisers you'd think would be good at grappling will now be the best at grappling.
The new rules just need more cowbell for them to work as reliable, functional, forced movement.
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Oooo that's a good catch. I like the fiction of it too; grab that retreating bandit by the collar and he ain't goin' nowhere.
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It's a decent tanking ability, arguably better for tanking than the current rules--since grapple+shove is less action efficient, and dragging monsters away from allies only works against monsters without a ranged attack--but it's not a terribly powerful tanking ability. It doesn't make the grappler any tankier--which grapple+shove does do--and it doesn't make the target waste actions (e.g. attacks on the grappler) to escape. The bigger downside, though, is that, because it's harder to maintain a grapple, the new rules are less useful for forced movement, which is, currently, the main benefit of using grappling.