That's why I'm saying fold the buffs in to their songs or add a different effect like: Enhanced stings- You gain x% crit so long as you have a DoT active on a target. Now I hear your concern about the single weapon skill, I'm going to disagree with you on it for Mch because, while they don't have that set rotation, they DO have ammo every 15 seconds (I think, is it 15? I can never remember) which opens up their options a little. Now as for brd and a single weaponskill, I don't think that's a bad thing and we should consider all of brd's abilities at level 70 where it matters. By that point they have all their DoTs and oGCD effects and cooldowns to manage. Even if we argue the loss of straight shot, by 70 it's only there to maintain a buff as any proc for it you will always want to spend on RA.
But let's take it another route instead of scrapping the ability. Let's make the crit buff passive (I will ALWAYS say it should be passive and will never change my mind, just a heads up) and turn Straight Shot in to a proc only ability with a high potency and then at 70 have the button turn from straight shot in to RA. Thereby teaching the new player at an early level to learn to watch for procs and use them, an essential skill for later on which would, in my opinion, make the class/job more intuitive. Would that be acceptable as a fair compromise? Make the button push exciting rather than "oh my buff is falling off soon, better hit that button."
You are correct in that they aren't quite the same as "maintenance buffs," rather my point was that if we absolutely have to have them and have no choice in the issue, make them a normal part of the rotation as Samurai does. In my opinion, that's better than having to stop my DPS rotation to push an extra button for a single buff.
I know you value player choice and agency and it's one of the most important things to you, having interesting choices and calls to make and such. But I don't agree on keeping that in the rotation and I've mentioned this before to you but I'll bring it up, say we get rid of Heavy Thrust right now (and buff drg moves the appropriate amount so they don't lose dps), what's really lost in that situation? What does that really look like? I'll tell you, when they get to a boss, the first button they hit ends up being the Impulse Drive combo instead of Heavy Thrust followed by the Impulse Drive combo. It's one extra GCD every 24(?) seconds for the drg, now it would be a net dps gain no doubt but that's why they can always tweak numbers. Having choice for it's own sake is not good design in my view.
Side note, slowly but surely I've noticed them moving away from choices in rotations and that things are slowly becoming more and more static. Pld, drk, sam, blm, and mnk are the ones that come to mind lately. Maybe it's just me.