Deploying Protraction sounds really interesting and could make for some great combinations with the SCH's and co heal's toolkit, like using the 10% to survive an aoe and the heal increase for a stronger Seraph shield for the next one.
Giving DT more purpose in general would be welcome. As taurus said, it's a button a good SCH rarely uses outside of phase transitions when you don't have a target anyway. I can also imagine it being interesting for Aetherpact, it would give the Fey Gauge a better purpose. Bonus points for an animation that looks like I have my entire party on a leash.
Protraction, Chain, Excog, Aetherpact and with decreased effect if necessary but it would add some real decision-making to DT instead of marrying it to Adlo and nothing else. 2min cooldown with a 2nd charge would be fair imo. I dislike skills that are married to one specific skills in practice, Zoe is guilty of that as well.