You're barely saving time by going the most optimal, so it doesn't really matter. Use what you find works best for that particular foe.
This. As a guy who mainly plays Lance in MHW, I can confirm that the greatest favor you can do for yourself and your team is to play what works, and what you're good at. Yeah, Lance isn't the most damaging weapon ever. Yeah, it's somewhat reliant on having either Evasion or Guard slotted in. Yeah, it's dead simple and all you have to do is hit RightFaceButton in patterns of threes.
But man, was it a godsend for me when fighting tougher monsters. I remember trying to fight Lunastra for the first time with Greatsword. Wow, did it go badly. I was getting tossed around like a ragdoll glued to the hands of a flaming monkey. Then I switched to Lance and laughed as my big piece of metal absorbed all of the damage the Lunastra could muster. And the chip damage dealt by fire and particularly powerful strikes? Healed effortlessly by my SnS bro rocking his not-at-all damage-focused Wide Range build.
By myself, I was a guy who patiently pokes things. By himself, he was an evasive little potion-chugger who slashed things and got the heck out. But together? We beat the stuffing out of Lunastra, tempered Teostra, you name it.
Play what you're good at, get a build that helps you, adapt when you have to, and fight your hardest. Nobody can fault you after that.