For the new upcoming events and S4 I would like to spice things up a little. I like the changeup in playstyle every now and then. I like different tile mechanics the most. Tile mechanics already differ in S3, some S2, Ninjatower, frostevent, sandevent and springevent from the normal. All of them except the mechanic in sandevent and some in S2 are kinda lame imo, since they arguably limit the options a player can do every turn instead of enhancing them, resulting in a less “puzzly” gameplay for the best move. Thats why i wish for cooler tile mechanics in the upcoming game modes 
Headcannon for cool mechanics: “Unbound!”, you dont have to make a match with your turn. “DoubleTrouble” make 2 moves each turn+ every enemyattack counter is reduced by 2 each turn, “Chargeup” play on a 6x7 grid, your first 3 tiles each turn deal no damage and grant reduced mana, “powerblocker” only tiles of 4 different collor appear, you may only use 3-4 heroes. “riot” every x turn your troops attack you instead of your opponent, “hostage” keep the hostage alive for as long as possible by doing minimal damage to it (on opponents side)
I’m looking forward to ideas you might have and wish for.