Previous Treks have had a great cast of regulars as well. Almost everyone on DS9 was a strong actor, and we had entire episodes where the focus was on someone other than the regular characters (like Nog/Vic in It's Only a Paper Moon).
I do agree with only 10 episodes they cannot afford that level of structural experimentation. But there's no reason to involve every single character in every single plot.
Take just as one example, the third episode this season, where they go on shore leave. The entire main cast goes to planet drunk/stoned, even though in several cases it doesn't make sense from a character perspective they want to get high. Compare this to say Captain's Holiday, where only Picard goes to Risa, and then gets in a solo adventure, with the main cast only appearing at the very beginning and ending of the episode. Everyone appears, but they mostly just get 1-2 scenes, because the real story is what happens in the middle. Even when DS9 did their (terrible) Risa episode, it focused on just a handful of regulars (Worf, Dax, Julian, Leeta, and Quark) with the rest of the crew staying behind.
Regardless, if you're going to tell a story which (at minimum) has to use Pike, Una, Spock, La'an, Chapel, M'Benga, and Uhura each week (and possibly Kirk, Pelia, and Scotty as well), they will be well-served by any sort of ship-based bottle episode (similar to Off Hour) where the crew is engaging in collaborative problem solving. Traditional away missions will never involve the entire crew, which means an A/B plot if you want to keep everyone involved. But if you want to avoid both of these, you're going to have to come up with some pretty tortured ways to keep everyone involved throughout the episode. Which is some of what we saw this season.
