I understand why they are doing this--we have tons of abilities as it is, and finding room for new ones is a challenge. However, with so many jobs being full of bloat buttons as it is, I would much rather they remove old garbage or try to fit these abilities into the job's existing gameplay loop than try to fit in new abilities as 'combos' that feel awful to use.
A few examples from classes I play often, from bad to worst:
AST:
Before DT: Divination was previously a reward for completing a card sign set, then was made into a standalone buff.
After DT: Still a standalone buff, but now combos into Oracle, a damage AoE of 860 potency.
Why this feels bad: In all honesty, Oracle did not need to exist, at all, and simply feels like padding they threw in to make sure every job had a lv 92 toy to play with. While some healers are clamoring for more DPS options, one button behind a 2m cooldown is probably not what they had in mind.
Suggested solution: Divination could be kept standalone and Oracle could be its own thing used as a reward for working your cards well... ah, they removed that part of AST. Honestly, AST is a disaster right now, and the last thing they need are worthless combos. In their attempt to make the cards intuitive, they removed all semblance of complexity from them. Oracle just feels like it exists as an obligation, to say "we haven't completely snubbed AST yet! see?! see?!". Get rid of it and I doubt anyone would miss it. Make sure the job is actually fun to play before layering garbage on top of it.
GNB:
Before DT: Was a 2m CD that was only used to refill the powder gauge.
After DT: Same effect, but now combos into Reign of Beasts -> Noble Blood -> Lion Heart for a total of 3,000 potency on a single target.
Why this feels bad: Bloodfest before was an easy way to chain together a ton of powder gauge combos, which were easy enough to weave with any needed mitigation. Now you have to account for the huge nuke in the middle, while being aware not to ruin the combo by doing anything else that starts one (Brutal Shell seething rn). Additionally, this is another case of '1 button spam combo' that afflicts some jobs, which does not feel good to play.
Suggested solution: The Reign of Beasts combo could have easily just been a Continuation chain with Double Down, similarly to how Gnashing Fang works. Not only does this free up use of Bloodfest, but it also fits better into GNB's general gameplay style. Lower the potency of the chain if needed to fit into Double Down's shorter cooldown, it would still be a sizable nuke.
Additionally, GNB is not dying for bar space, especially after they crammed Sonic Break into a combo with No Mercy (also a change I dislike, but another class has the same problem but worse later in this post). Of all the classes, it is one of the least in need of consolidation.
SCH:
Before DT: A debuff on a single target that makes crits 10% more likely against them.
After DT: Same effect, but now combos into Baneful Impaction, an AoE DoT.
Why this feels bad: Of all things to stick behind a 2m CD, an AoE DoT is one of the strangest. Chain Stratagem, being single target, was generally saved for boss encounters. Now, Scholars are looking for strange ways to fit it into trash pulls to get actually decent use out of Baneful Impaction. This can cause a cooldown desync where CS isn't ready for a boss encounter, which limits its usefulness as that is generally when people are dumping their nukes.
Suggested solution: Scholars have been asking for more DPS tools for years as their healing kit is generally very solid and leaves decent downtime. Just give them Baneful Impaction like you gave Sages Eukrasian Dyskrasia.
If not by itself (because SCH is a little tight for button space), then make it a combo behind Energy Drain. If that isn't good, then pehaps get rid of worse-than-trash Fey Blessing to make room for Baneful to be its own button.
SB's strict adherence to the 2-minute meta is starting to result in strange choices, as if whoever has their hands on class design thinks that jobs should only be able to be fun or impactful once every 2 minutes. Please note that every ability listed here with a combo added in DT has a 2-minute cooldown...
Is this where we're going in terms of job design? New abilities being relegated to odd positions hidden behind utility cooldowns? What's next? Presence of Mind comboing into Afflatus Obliteration?
Oh, wait, they already added that...