One idea I’ve been kicking around is a slight tweak to matching, combined with an improved raid tutorial at the outset. Most of the frustration I see comes from one of two sources. The first one is a lack of understanding of how raiding actually works, the matchmaking and the mechanics. The second is consistently being matched with players who appear significantly more powerful than you.
An improved raid tutorial would address the first issue, at least somewhat. It would need to explain clearly and succinctly how opponents are chosen and how the cup awards are determined. It would need to cover how each team gains mana and how both normal and special attacks work. It should mention that buffs and debuffs override others of the same type, and that the AI goes from left to right. It should also stress that team power levels are only a rough approximation, not a hard and fast determination of who should win.
A tweak to the matchmaking would address the frustration of being overmatched, especially at lower levels. Currently, you’ll be matched with someone who has within 300 cups of your total. This mechanism is easily manipulated by dropping cups to give much easier matches, thus allowing the stronger players to prey on the weaker ones and fill their chest without fear of being revenged. A couple of small tweaks to matching could change that without requiring a large change in the coding. First, make raid arenas a reflection of the highest cups a player has won, rather than their current cups. If you’ve won enough cups to hit Platinum, you’re a Platinum player regardless of your current cup total. Your raid chest tier would still be determined by your current cup total. Once your raid arena is determined, your pool of available matches will be drawn from players who are no more than one tier lower AND within 10% of your current cup total. So for example, if you’re currently in high Gold at 1750 cups, but raiding up into Platinum to open your chest, you’re a Platinum player. Your raid opponents would be players from Gold, Platinum or Diamond arenas with a current cup total of 1750 +/- 175, or 1575-1925. If you decide to drop cups down to 1000, your opponents would then be chosen from Gold arena or higher players with a current cup total of 900-1100. You’d be facing other cup droppers with easy defenses, so you’d still be able to fill your chest, but they’d have a fair chance at revenge. You wouldn’t be matched up with Silver arena players at all.