Thought on banning Multiclassing?

I'd flair this as 5e / 5.5e if I could, but oh well.

I've been compiling a big list of my houserules and noticed that a large portion of them could be solved via banning multiclassing (side note here: yes, in 5e multiclassing is an optional rule, therefore a GM is always free to just "not let it through", but it was so widely accepted that it was presumed it was on the table at all times; in 5.5e, however, it has lost that moniker, so now it's considered more of a baseline that has to actively be banned. I'll be using the word "ban" from here on just to save time), and that got me thinking: have others done that and how did it work out?

From my PoV, the pros are the following:

1. Removes cheese builds, the most obvious being people who take level 1 in Fighter and then go X levels of a caster class, since that allows a character to have proficiency in heavy armor and still be able to cast very heavy-hitting spells. So instead of having a glass cannon Wizard or Sorcerer, you have... a standard, metal cannon.
2. Allows for more creative homebrew dedicated to each class without worrying about things like "BuT wHaT iF tHeY mUlTiClAsS tHiS aNd ThAt and break my shit?" I'd really love to give a lot of love to a few classes I personally deem as a tad subpar, but multiclassing always seems to rear its ugly head and kill my enjoyment for that sort of stuff.
3. Possibly making more feats way more appealing to take. I myself would start looking at things like Lightly Armored if I couldn't just 1 lvl dip into Fighter to get up to medium armor for basically free.

And, again, from my PoV, the cons are:

1. Banning is kinda boring? But so is cheesing the game, so they probably cancel out.
2. I know that sometimes you NEED to multiclass in order to attain a certain flavour fantasy you might want for your character (i.e., a Paladin / Warlock "Witch Knight" archetype; think Arthas from Warcraft III), so outright saying my players can't do that in my games feels just outright bad.

So I'm looking for advice on the topic. Oh and spare me the "just make it so a multiclass needs to narratively make it sense", because it's comically easy to come up with an explanation for any multiclass combination. I need to make it a hardset rule: allow or disallow, no ifs or buts.

Thanks in advance!

Honestly it's fun so I would say no, but leave the option for broken things like the coffeelock etc

There's always a downside with multiclassing, if you take that first level of Fighter you are significantly behind other pure classes in the early levels etc

It depends what your concerns are. You seem to take balance quite seriously, but multiclassing is infinitely more balanced than the overwhelming majority of homebrew. I'd allow multiclassing before any homebrew.

Yeah, it needs to narratively make sense. I know that’s not what you want to hear, but that’s the answer you’re going to get.

He's not wrong though that it is hilariously easy to make it make sense narratively, so it's not a real restriction. He's clearly concerned about the mechanical impact and not the narrative one.

Your game, your rules, but before banning multi-classing you have options. If you're worried about min-maxing players, that's an OOC conversation. If your players want a specific build idea from a multi-class, then figure out whether that's something wholly decided by a multi-class option or if they can use feats or such to get where they're looking for.

And if otherwise, make it cost something - time and energy but also maybe money or a side quest.

It sounds like you just need to find players that aren't just about cheesing the game? At the same time, why not just do another audit of your home rules and compare them to official rules because if I had to guess, either you're misremembering some rulings, accepted common community interpretations that might not be official, or just don't say enough to shenanigans.

other games don't have multiclassing. if DnD is boring you with that feature you should consider a different system. If your staying with 5e anyway, don't discard that part, because thats somthing that is kinda special that 5e does. im learning draw steel right now and its a game that explicitly chose not to allow multiclassing so that each class could be ass bad ass as it can be without having to playtest out broken builds.

I am running a mmorpg style campaign now and I just banned it. My campaign have around 20 players which is a mix of newbies and experienced players, I don't want the newbies messed themselves up with the idea of multiclass and don't want the crazy build from experience players ruined the expectations of the new players. Flavour is free, if a player want to play a which knight they will be totally fine for monoclass warlock or paladin.

I don’t allow it. Optional rules, I decided to not allow it.
If they want to attain a certain flavor, ok. Work with me from the get go. We can come up with a subclass to meet your needs.

I think in 2E, the heavy armors made casting Spells impossible. Metal interferes with magic forces or the armor wasn't flexible enough for the Somatic movements.

To add to your "just make it so a multiclass needs to narratively make it sense", because it's comically easy to come up with an explanation for any multiclass combination" part, whilst that's true, it is also the most logical.

I've told my players that they won't be able to multiclass into any class they can't get training in. As an example, we have no wizards, so they can't just decided to become an X Wizard because who will show them?

If they want to do this, it's going to take finding a wizard to train them, or a trip to the University to study, and it's going to take X amount of time an Y amount of gold. This then can open the door for a sidequest etc

Now, if they want to Multiclass into say a bard, then sure because we have a bard in the party, so during long rests/downtime, she can teach them how to sing/write etc.

It limits it, but doesn't make it entirely impossible.

Same with level ups. My players when they level up can't just get their new found skills and power. They have to take a long rest, and then we RP on how they get stronger. Lock's patron whispers to them, Fighter trains yadda yadda.

At end of the day, it's your game, you run it how you want. But the players also need to have fun otherwise it's all for nothing

Yeah ban it.

One of two things happen with multiclassing.

Either they find an overpowered combo and out pace the rest of the group.

Or they shoot themselves in the foot and feel useless, falling far behind in terms of power level.

If anyone expresses interest in features or abilities beyond the scope of their class then you can easily homebrew a blessing from a god or something as a quest reward or customize a magic item to scratch their itch. It's not that hard.

D&D isn't a very balanced game. Multiclassing can just as easily prevent a martial character from falling off and help make your party more balanced. Let them have fun. Their build probably won't be stronger than a full wizard anyway.

Not a fan of house rules that ban things that are officially allowed by the rules and don’t harm anyone else. It’s up to you to know what’s on your players sheets and balance combat for that (as well as sometimes letting them have their multiclass fuckery win) blah blah blah Silvery Barbs.

I think house rules are there to make sure everyone has a good time: crunchy crits, death saves behind the screen to build suspense, PvP based on what the table enjoys.
Some people’s good time is playing a ridiculous build.