So, I've been mulling this over in my head, because I remembered what it was like in the days when my group didn't follow the old ways (lol).

Way back when, the normal way that I knew of spell users getting their spells among most groups was they just picked what they knew. We used to place import on spell books then, so when they got a new spell known at a certain level, they would just pick the spell  and add it to their spell book.

However, that wasn't the way we were supposed to play 1e. The offical thing was they got to start with a few spells and then after that they had to go and find them.

Now, back in the 1e day, it wasn't quite as critical -- it wasn't that the classes were "more balanced", it was that they all did things differently, and at higher levels Magic-users could still wipe out small armies. The thing for balance was actually supposed to be that they have to find the spells.

A few years before 5e came out, we switched over to a "find your spells" system. It means I have to be much more watchful about my treasure hoards and such, and remember to reward folks with magical scrolls and useful stuff, and maybe drop a few spell books here and there to give them extra spells. And we loved it. I had a 16th level Wizard at one point in one campaign who had three cantrips, then a few 3rd levels, then some 5th level spells, and was constantly going out to research new stuff. That was his entire reason for adventuring, He didn't want to go fight monsters or anything, he just wanted more spells. If there wasn't likely to be a spell, he hated the idea of going.

This is obviously not going to be popular with a lot of folks who just want to pick and choose their spells -- but for role playing and beign heroes and for DMs who are having a hard time finding balance, remember that this is something you can do.

This leads me to the next thing. Because we did that, we have a catalog for our table of like 300 spells lol. All of them created by our players. Some are just reskins of existing spells that someone never found, others are completely original sells, and some are house versions of spells that folks found in the internet and liked.

We have a few different rulesets for how someone creates a spell. In one game, all spells are created "on the fly"., and in the moment. In another, they are carefully researched, cost a fortune, and take multiple grimoires to figure out. My own system is a custom one, and then there are a few who have a basic simple one straight out of the books.

Because that, in turn, goes with the idea of limiting spells. We thinking of Bigby and Tenser and Otiluke and Tasha because those spells, created in the early years, became normal standard spells in the original games, and we can do that ourselves.

So, I was curious what other people do these days.

Having to find spells sounds interesting but it wouldn't work well when the most popular classes like Sorcerer and Warlock thematically are supposed to get their spells without having to do anything to earn them, and then classes like Wizard that are supposed to be studying for spells are literally never played (at least that I ever see).  It would just make the imbalance even worse

If they want to homebrew spells then I would go with the following:

1. Reflavouring existing spell or a very minor change? No problem. Just let me know, and it's fine. I have some 'minor edit' rulings that are auto-approved.

2. Anything else: we need a discussion. 

As for gaining the spells once approved it follows the same rules as the class permits. Full prep types: you can prepare it as normal. Level-up types: you can select on level-up as normal. Wizard (or any other mixed-type that may crop up in future): you can choose the spell when levelling up as normal, or you can craft the scroll as if you already knew it then scribe the spell from scroll at the discounted rate, alternatively it can be a scroll you find in the next loot drop, if you don't care that it was your character who "in-lore" invented it.

If something remains reasonably balanced or if it has no mechanical difference, there is no reason to say no or be fussy about it. Like if a monk or fighter or whoever, with extra attack, who makes their 2 attacks, both hit, but want to describe it as a flashy 4-hit combo? Fine by me. It's still only 2 attack rolls, the damage rolls are the same, so why care? Maybe they want something like eldritch blast, but instead of magic bolts, it's conjured metal balls and does bludgeoning instead of force? Absolutely fine and dandy. 

Let's take an example from Critical Role Season 2 (spoilers)

 It's a great example of taking something already balanced in the game and changing it in a way to be more personal and still remain balanced. It adds a lot more of the character into the spellcasting which makes it more immersive and more fun.

I'm totally down for that.