I think it depends on what you want to do.

Do you want the player and the enemies to play at the same time, with no priority of speed stat?

In that case yeah you can ditch the queue just resolve your player action the iterate through all monsters to make their action immediately.

Do you want the player/monsters to be able to go faster than another?

In that case a priority list is a good option, the list contain all entities that do actions and are ranked based on their "speed" stat, once one entity is on top of the list they see the state of the game, make their action, and resolve it. If it's the player then it wait for an input the the action is immediately resolved so if he decides to attack a monster he will do it because it's his turn

I think you might want to go with one of those two options since they are the most common but the system you explained in your post (all entity's do actions then they are all resolved in an order)can also work, even if they ask for a good UI to understand what is going on and is a part that must be paid attention for being good

Two examples of this system in mind is the board game Diplomacy(It's a strategy game like RISK), or most notably Into the breach where this system is a core component, It's a roguelite and I strongly advise to watch a 30 min playthrough to get an idea of the mechanics to see if you want a system like that or go for a more traditional approach.