I dunno man, you’re describing a Dragon Ball fight progression. PC should be professionals who don’t take chances.
For a Gladiator who is wowing the crowd power abilities sound great but there is a lot of showmanship in gladiatorial fights.
Not so much in grim life or death struggles.
Yeah, but 5e is definitely a lot of things ut it is not grim life or realistic. 5e is super hereo in fantasyland. It seems more cinematic than earlier editions to me.
And so having structually anticlimactic battles is ... sad. Like, in the last campaign I DM'ed the group had to lead a city under attack against an amphibious attack with a big kraken. So that had some set pieces fights against smaller scale enemies inside the city, using up some ressources and then they went after the kraken, who destroyed most of the fleet defending the city already, leaving the characters as the last line of defense. So far so good. A battle with rising tensions, very cinematic and now we are reaching the climax, the final encounter if the battle.
Our characters on their small ship against a freaking Kraken (fir which they where underleveled) - so they make the only sensible thing that makes sense in 5e - the go in the first rounds NOVA on the Kraken, using up the highestspell slots and rare and very rare single use magic items (like a candle of invocation to open a gate to summon the god they are allied with).
And in the End, the Kraken gets killed by a cantrip, because by then everybody was drained.
The whole battle started strong and ended on a cantrip, because in the End that was the only thing left, the characters could do. Cantrips. Very anticlimactic. Very uncinematic.
If I would redo the battle now, I would change some things- if I would do it RAW, I would maybe create a magic item for the group, that they would need to charge during battle, that can ensnare the encounter or at least quicken it, so that it doesn't end in a cantrip slugfest.