Chaosmancer
Legend
I'm not quite following your logic. Let's just throw Battlemaster, Samurai and Cavalier up on the block. We'll assume 3rd level and an 18 strength for all of them (which is really hard to pull off, maybe even impossible, but hey, the dice loved you)
Battlemaster at 3rd level gets a tool prof and 4d8 superiority dice they can use on 3 manuevers per short rest
Cavalier gets a skill, a ribbon mounts ability (ignoring because mounts will always be rare) and their mark. The mark will always give disadvantage to enemies but 4 times per day you can make a bonus action attack, with advantage, and get +1 damage to it, if the enemy attacked someone other than you
Samurai gets a skill, and 3 times per day they can get advantage on their attacks and gain 5 temp hp.
Now, looking at this, who is more likely to get a Nova? They all get 3-4 uses of their ability with zero rests, but a short rest will give the Battlemaster another 4 dice, and if we assume a second rest that gives them another 4 dice. That guy is more likely to have some maneuver dice left to use against the boss than the Cavalier or Samurai are to have their stuff.
Now, maybe you could argue that the Cavalier's mark, since it is constant, having a handful of bonus action attacks could be useful, but they have to be triggered by an enemy attacking an ally, and they compete with other bonus actions like Shield Master, Dual Wielding, Second Wind, ect and the bonus damage is kind of weak until you hit higher levels.
And even if you make that argument for the Cavalier, what can you say about the samurai? Is 15 temp hp over the course of an entire day really that good? You're gaining it in groups of 5 and I think most fights the fighter is likely to take more than 5 damage, so it helps sure, but not a lot, and the advantage seems really good... unless you are playing with flanking, or a bard who casts faerie fire, or a caster uses their familiar to Help you, or use shield master, or any of the plentiful ways of gaining advantage. I'm playing a barbarian, I rarely use Reckless attack and I almost never attack without advantage.
And, maybe we could argue that 15 hp at 3rd level is decently powerful, but it stays at 15 hp until you hit level 10, so is it still worth it at level 8? When the bard takes inspiring leader and gives everyone 13 temp hp a rest anyways?
So, no, I don't think this is so you can Nova more often and it be more cool, because the short rest abilities of the battlemaster are equal if not more powerful than anything these two classes can bring to bear, and their long rest means you are less likely to be able to Nova during a standard adventuring day.
I know I can house rule this, and I definitely plan to, but this is such a strange design decision that I really am trying to understand why it is the way it is before I just change everything back to the way it was.
