Shove is an interesting mechanic in BG3, but also extremely powerful.
In way too many occasions in the game, shove becomes a "Save or Die" spell. All you need is a nearby chasm - but there's a fairly big amount of chasms in the game. In fact, around many bigger chasms, you'll find monsters and enemies that have high strength and/or abilities to shove you into a chasm. But even if you dodge a minotaur who's bull rushing you, they don't charge into the chasm. Why? Because deciding an encounter in a strategic rpg with 1 dice roll is rather silly.
There's a level 9 spell in D&D called "Power Word Kill". It has gone through several iterations over the years, but in D&D5, you point at someone, and if they have 100 hit points or less, they die. If they have more than 100 hit points, nothing happens. There's a reason why you have to be a level 17 spellcaster to have this spell: It's powerful, and at level 17 most enemies easily have more than 100 hit points, so it ends up not being as powerful anyway.
Is it awesome to shove enemies into a nearby chasm? If you don't care about their loot, sure. Is it too powerful? Yeah, probably.
You might argue that the very natural conclusion of being pushed into a chasm is death, and I would entirely agree. I would also argue that picking up an enemy and throwing them into a chasm would result in their death. My barbarian friend and I tried this. The game didn't allow the picked up enemy to be thrown into a chasm. Probably because it would be too powerful. In the end, it's a game, and abstract concepts like someone's "life force" is simplified into hit points, so even if you slash your Greataxe at someone's neck, they don't necessarily just get beheaded and die instantly (unless you deal more damage than the entirety of their hit points, in which case a beheading could absolutely be the outcome)
First of all I would suggest removing the option shoving someone into a chasm. If you do think it's a central part to the game, at least give the entity being shoved a DC10 Dexterity saving throw (this could represent something like catching the ledge). Give advantage to anyone who's under the effect of Feather Fall (after all, it's easier to react to the situation if you're floating). I don't know how the shove affects anyone with Fly, but obviously anyone who can fly can just fly back up. Anyone with Misty Step should probably get the opportunity to teleport back up, and I'm sure there's plenty other spells and abilities that should save you as well.
At the very least I would suggest a checkbox in the options to add/remove chasm-shoving.
