Form Shift, Meditation, Forbidden Chakra, Purification, Tornado Kick. These are all examples of skills that would be completely worthless if Greased Lightning wasn't a pain. "Bandaid fixes", as you might call them. If the boss does not ever jump, they are completely worthless. In fact, Tornado Kick now has anti-synergy with many of those skills and Riddle of Earth. Well, I guess Forbidden Chakra does get some help in the expansion, but still.
I'm not saying that skills shouldn't have synergy or shouldn't be meaningful. But they still should be something you feel good about using. Do you feel good about using Riddle of Fire? Maybe, even though the attack speed slow down breaks the flow of the spec and makes it feel bad to play as. Are you excited about Shoulder Tackle doing 30 more potency? Are you excited about your double dash being locked behind Fists of Wind, which would mean that you'd have to give up on your damage bonus, which means you'll never be able to take advantage of that? There are many ways to have actually good abilities that feel good to use rather than feeling like there is a whole army of abilities designed to make an annoying class mechanic feel slightly worse. If GL3 caused Monk to deal insane damage, sure, maybe it'd be worth it. But it's just a maintenance buff that allows Monk to perform on par when accounting for raid utility, pretty much. And what's even worse, it's not even a complicated maintenance buff that requires any thought. It just is there, automatically. You're completely at the mercy of encounters. And, again, instead of changing the skill itself, they get billions of bandaid fixes that only are useful if the encounter design screws Monk over to begin with. A sustained fight that should play to Monk's strengths? Half of your 50+ toolkit does nothing.
Elixir Field is in my opinion easily the most fun Monk skill in HW / SB, and what does it do? 220 potency AoE, nothing else. It doesn't need to be extremely complicated and there does not need to be a massive trade off of losing GL3 or lowering weaponskill recast speed. As a simple example, you could make an oGCD ability that's relatively weak but has a damage bonus when used during Opo-Opo form, for instance. Didn't get it? No big deal, you just dealt less damage. Got it? Nice, more damage, feels good! An oGCD ability to make Twin Snakes or Dragon Kick have double the duration for the next attack? Nice, planning required, a rotation change required, a DPS increase and no trade off elsewhere if you get it right. Another example: oGCD ability that says "If your next weaponskill is a critical hit, instantly gain 3 Chakra". Planning required(Save for Bootshine, don't waste Chakra), no rotational trade offs, still impactful when you get it right.