[RPG] What problems may arise from the house rules on grappling and restraining

Introduction

I am dissatisfied with the rules for grappling in 5e. Well, it's more that I'm dissatisfied with the fact that there's no way to restrain someone in 5e via grappling.

The rules, as they are (if I imagine two humans having a fight) are better to describe someone grabbing someone's arm, or by the scruff of the neck, which may prevent them from moving (unless they "break the grapple"), but otherwise doesn't prevent them from doing anything else, because the Grappled condition simply reduces the grappled creature's speed to 0.

If that is the player's intent, then those rules work fine; you use an attack (not Action, just a single attack) to try to grab someone, with a contested check. If you win, now they can't run away. That's fine.

Problem

However, what about if someone wants to restrain someone? I can imagine it would be easy enough to grab around someone such that their arms are pinned to their body, making them effectively Restrained. However, RAW, there is no way the average PC can do this; they need to have taken the Grappler feat, and even then, it takes two attacks to do so (so unless you have Extra Attack or Action Surge, it takes two turns to actually restrain someone).

The problem I'm seeing here mainly concerns new players who just want to grab the enemy and restrain them, but the best option that's available to them is the grapple, which doesn't do anything like what they're imagining. For this reason, shoving and other alternatives do not solve this problem because that's not what the new player wanted to do, despite the fact that anyone can try to restrain another human IRL. They'd be like: "What? I could restrain you, and I'm not even that strong, so why can't Conan the Barbarian restrain that bandit without taking a feat?"

Since I don't like the fact that a PC cannot attempt to restrain someone, despite the fact that it seems like a reasonable thing to attempt, I've tried to come up with something to make restraining a target possible, especially for new players for whom trying something like this might seem intuitive, but then the RULES get in their way. The amount of times I've seen a new player try to grapple the enemy, thinking it'll actually do something, only to find that in practice it did nothing and the creature just attacked them anyway without penalty, and without giving anyone else the advantage they were expecting it to…

Proposal

Anyway, my proposed house rules are that, on top of the existing rules for grappling, you can also:

• spend your Action (not an attack, your full action) to attempt to Restrain a creature.
• Not just any creature, only a humanoid creature, or a creature that is roughly humanoid (like, say, a zombie, which is "undead", but a normal person attempted to restrain one would still intuitively understand how to do it).
• Both creatures are then restrained, as per the Grappler feat, but this is something anyone can do.

The reason for the restriction on humanoid (or humanoid-like) is because I, personally, could give restraining another human a pretty good go, but I wouldn't know how to go about restraining a dog (note: I do not own dogs, so maybe dog owners would know how to), let alone a Basilisk or a Spectator or something that one might encounter in the D&D universe.

Note that my proposal is not intended as an alternative to teaching new players how grappling actually works, but simply providing a way to do something that basic grappling doesn't quite cover (specifically restraining someone).

Grappler feat

Of course, this seriously nerfs the Grappler feat, so I've adjusted that too.

• Firstly, it should lift the restriction above; a "trained grappler" should know how to restrain a dog, Basilisk, Spectator, or whatever else can be grappled RAW.
• Secondly, they can restrain someone with an attack, not action, which is also an improvement on the RAW Grappler feat, which takes two attacks (potentially two turns, although most likely a character that would take the Grappler feat is also one who is likely to have Extra Attack past level 5).
• I was also considering adding "able to grapple (just a normal grapple) as a bonus action", possibly instead of the previous point (so you can restrain using your bonus action and one "attack"), but I was wary of treading on the toes of the Tavern Brawler feat, so I'm not sure…

Question

Given my proposed house rules, I hope that it:

1. gives an option to players (I mostly have new players in mind who don't know obscure rules like how grappling works) to be able to sacrifice their turn to restrain someone,
2. for it to be balanced rather than a "strictly superior choice", and
3. to still have the Grappler feat be a worthwhile investment for a "grapple build", such that it's not a "must-have" that out-muscles any other feat, but also not that it's basically useless with my new "Restrain as an Action" house rules.

Are there problems with my proposal that I'm overlooking that will make my new "Restrain" Action massively overpowered, or my revised Grappler feat massively over- or under-powered? I just want a sanity check on what I've come up with before it "goes live" in my games.