Bonus Stage
Trial
Each section would have 3 random sub-sections from all 4 original sections, with an orb amount based on what sub-sections it's made of. The randomness from this would make it harder for you to anticipate your jumps, eventually leading you to fail.
Rewards
More Enemies/Coins would spawn as it progresses, an additional random box would be added every 2-3 sections, and the chance for a Sword chest would increase gradually.
Chest Hunt
Trial
Mimics would no longer spawn randomly, and instead would be shown off the start, and be randomized in a similar way to those games where you have to remember in which cup the ball is. But because it'd be insanely hard to follow 4 mimics in 30 chests, and it'd take very long, it can instead be reduced to 10 chests and 2 mimics. After each CH, the shuffle would be faster and longer, until the speed eventually becomes too high for you to follow the mimics properly.
Rewards
Every bundle of 10 chests, coins and souls rewards would be increased, multipliers would have a base increase of +1, and the chance for an Armory chest would increase gradually.
Ascending Heights
Trial
In addition to the platforms getting more spread out in the original minigame, spike platforms or falling rocks could be added as extra danger to avoid, meaning you'd have to focus on more than just not falling down. Moving platforms could also go faster as the game goes on.
Rewards
Every 1,250m, you'd get a chest that would give increasing Coins, Souls and Frozen Shards rewards, and a higher chance for a Dagger chest.
Boss Fights
Trial
Bosses would no longer have a health bar, but a damage meter instead. Every time you deal a certain amount of damage (for example, 500), attacks would get faster, until they're so fast you become unable to dodge them.
Rewards
Each time attacks get faster, the stats of the Ring become better. (Higher chance of Excellent, additional bonuses, and additional levels)
It might need a rework of the armory chance system, but the increased stats of Armory items could also be applied to minigames, along with the higher chance to get an armory chest drop. And for the sake of balance, having the same performance as you normally would without Trial mode activated would give you lesser rewards, so that you wouldn't go Trial mode every single time if you're not sure you can make it.