I prefer the right one. I have played many games where the player easily curb-stomps everything *cough*2D Mario games*cough* with no differences between installments. We want strengths, but we want weaknesses. We don't want an ultra-niche strength that never appears and then carry a bunch of common weaknesses. We want useful strengths that can be usefull in many situations, but weaknesses that are shown in several places as well. At least Sonic is afraid of water, meanwhile Mario can flipping breathe in there, holding zero weaknesses, or even character.

I'm gonna use my Lucario in Pokémon as an example. Teach it Aura Sphere, tada! You now have your powerful fighting move. Now what, since the offensive Steel type moves he learns are worthless? Psychic, for example, lets him counter Fighting Pokémon, one of his weaknesses. Rock Slide lets him counter Flying and Fire Pokémon, some more of his weaknesses. Earthquake lets him rofl stomp on non-flying Pokémon. Dragon Pulse lets him do normal damage on most enemies and double damage on Dragon enemies (aside from Dialga). The main situation of what moves you want your Pokémon to learn is whether you want Rock Slide or Earthquake, since Rock Slide isn't good on Ground Pokémon but Earthquake doesn't hit Flying Pokémon. Maybe you want Extreme Speed instead. Or possibly Protect and a stat raising move. I could go on about IVs and EVs, but I'll spare you from that poisonous barb.

That is where the main components of fighting play along: being unique, being balanced, and being partly similar. The first and third should not be able to contradict each other.

Pokémon can be unique by:
-the moves they know
-their trait
-their ability
-their stats, such as HP and Sp. Atk

Pokémon is balanced because:
-powerful attacks have limited PP, or give nerfs to user
-weak attacks have plenty of PP, and can nerf the opponent or buff the player
-Protect and Detect are strategic but can't be chained. Some moves can also hit them.
-held items can focus on buffing stats, or doing special effects, such as the Quick Claw
-Ever used Earthquake on a Pokémon about to hit you with Dig? Or Surf on a Pokémon using Dive?

Pokémon are similar (something between 2 Marowacks or Gallades) because:
-the moves and TMs they can learn
-the abilities they can have
-the type of stats focused on, such as electric types having a lot of speed, and steel types focusing on defense

Again, this is just an example, but in the world of SK LD, everything is revolved around the following:
-gear, such as OP polaris
-UVs
-latency
-how focused you are on capturing
-whether you hold a Striker Pack, a Recon Cloak, or the useless Guardian Shield
-trinkets

Uniqueness, check. Similarity, check. Balance, because we already beat THIS dead bush too much, NOT CHECK.

Now let's take a look at your suggestion. It looks great, but it is a few Cheerios short of a bowl. There is balance since there are no unfair advantages. There is similarity between classes. However, there is no uniqueness between classes, and the flaws lie here. There needs to be an option to choose between a Leviatian and a Suda or a DVS. The option of AP or Valiance or Alchemers. The option of Nitronome or Shards (ever put four of them in a big group?) or Venom Veilers. These would be provided, but if we get too far into it we would go back to our current LD system that reeks of garbage. Something would have to prevent Combuster charge spam (I admit to this gladly) and Shivermist spam and Polaris spam. Okay, at least Combuster charging requires movement and timing. Shivermist spamming is countered by either a gun or freeze resist. And Polaris is mere point and shoot mechanins with no joy. Especially if all you do is Shivermist spam and when someone comes you pull out your Supernova (since shock breaks freeze) then go back to shivermist.

What would prevent this "no uniqueness" mess? The following weapons will all deal normal damage, be provided to all, and only the following weapons are able to be used:
Swords:
Leviathan Blade
The elemental 5* brandishes, and Acheron (no Obsidian)
DVS
The four Flourishes (not the candy cane though)
DA and GF
Suda and Triglav
FoV
Not useable:Cleavers, WHB, Winmillion, Obsidian Blade, DCP, WRH, Lionheart and Scissors

Guns:
Valiance
Blitz, Plague, and VP
The five main drivers (no egg nog for you)
Biohazard and Neutralizer
NO Polaris or Supernova
AP and Sentenza (no Carbine)
Callahan
Not useable: Eggnog Blaster, Polaris, Supernova, Obsidian Carbine, Iron Slug

Bombs:
Nitronome
BAB
Irontech Destroyer
non-Obsidian Vortexes
Mist bombs (except for the Winterfest ones, along with Shivermist)
The six shard bombs
DBB
Not useable: Jack Frost, Scalding Cocoa, Grinchlin-suprise-box-bomb-that-clones-VV, Shivermist Buster, Obsidian Crusher, DR

These weapons will only be in their 5* forms, and, again deal only normal damage. They would have damage equal to lvl 10 and all have CTR Med.

One may ask "B-but how would OOO make money off of LD now?"
Simple. If you own one of the weapons listed up there (the 5* counterpart only), the damage you do with that weapon increases by 10%. Not OP, right? Owning more of these, or any with UVs will not apply UVs or apply bonuses past 10% damage. Everybody gets the same normal defense armor regardless of class. There, now OOO gets money from players buying more 5* gears.

TL;DR Read the text or I will push you off the curb. Why do you even need a TL;DR? If you NEED it, why are you on the forums?