This would've worked OK in the first game, but the way they changed the skill trees (needing to level up each individual weapon to unlock it's skills) kinda makes it an incentive to specialize early. I will say that in the first game, I stuck to 3 weapons, and only 3. Only reason I played with any others was to get Plat. I planned on doing same here, but the change kinda convinced me to give each a fair shake. Now I've grown to really like the Odachi, and really enjoy the Switchglaive, and to a lesser extent the Hatchets. Hell, I even don't mind the Axe now. Still don't care for the Spear much, but maybe I'll eventually come around. So you branching out to other weapons already is good shyt. And you won't get greens until you beat the game.
Your above opinion on this vs. Sekiro makes a little more sense too. If you're not even using skills, you're not unlocking the full potential of this game at all. Once (if) you figure out how to stance dance, and chaining skills (not only with one weapon, but chaining skills with both equipped weapons), and switching weapons not only mid-fight, but mid-attack, and mastering Ki Flux 2 so that you can keep the pressure on the enemy without having to constantly back off. Like I said, the combat is so deep, but you gotta be willing to dig a bit and learn. I know a lot of folks don't wanna go that deep into games, especially these days, but the payoff with this game is worth it IMO.