I have no issue with it, fine to play it.
That being said, it is a weaker poker mechanism.
There is the randomness factor - similar to derailment. There are some key differences between the two: derailment you have much more information, and you’re able to ascertain and judge your strength and position on 3 boards, knowing where you are pre river (how do I feel if top board goes away, middle, bottom, 2, or all 3 stay).
For something like Omajack, unless you are either nutted pre river OR have an immensely strong hand that should remain strong regardless (aces suited + X with either flush coming in giving you 21 or close), then the river very much randomizes everyone’s strength.
That aspect is not at all similar to detrailment and I can’t think of other mechanics that are similar, unless someone applies locust post river card - which again, no one would play.
As a mechanism, it is not borne of or related to poker. It also feels much more akin to side bets or running bets - ie $5 for red boards, $10 for X on the river where everyone has a number, etc.
Scarney, high pips, low pips, 0 games, etc. are building to a defined up or down - your 21s, baccs, etc. are all bringing in a mechanism that isn’t a poker variant, but just that - an unnatural to poker mechanism.
Is it bad? Is it good? Up to the masses.
Personally I think it can be fun to switch things up once or twice, and I’m happy to play any game called (except shuffle mechanism), but I do think it’s obvious how from a game building operations and mechanics perspective your omajacks, baccs, etc. are simply weaker/worse.
I fully believe if you took non poker playing board gamers and game architects, let them learn and play out the variations, they would mostly come to the same conclusion.