"be more explanatory" is correct and usable in written English.
You can use it when you want someone to explain something in greater detail. For example, "Can you please be more explanatory about what you are asking me to do?".
It needs more iterations to be more explanatory about why a certain analysis did not work.
The structural space analysis proved to be more explanatory regarding the shifts and changes in formal discourse, by combining structural measures and looking beyond the core of the network structure.
(If van Fraassen were to object that the former is not really more informative than the latter, or at any rate not more informative in the appropriate sense whatever that is then we should certainly refuse to grant the premise that in order to be more explanatory a theory must be more informative).
Truth be told it is easier to be declarative if you are a challenger, as Obama was in 2008 challenging the Bush/McCain policies, than if you have a track record that didn't live up to grand promises and for which it is difficult to re-declare and for which you instead need to be more explanatory.
Column headings in the tables and data sets should be more explanatory.
A trial intended to inform a research decision about the biological effect of a new drug is likely to be more explanatory in design.
They were more explanatory than critical.
The rules are more explanatory, however, if they show that these phonemes behave in a similar way because they form a natural class, or set, whose members are defined by a common property.
"It is true that I might have been more careful in the past," he says, "but we are always far too eager to identify a single cause - usually a human action - in the hope of picking out something that is more explanatory.
At times building methods are demonstrated simply by exposing the structure, as in the heavy timber frame, but in many styles the functions of structural systems have been interpreted by designing their members in forms that often are more explanatory than efficient.
Google's Welle admitted that the company's unconscious bias training is more explanatory and "not very practical". Google has built a second workshop that trains people to step in when they see biased interactions, but it's just getting rolled out – only about 5% of their employees have gone through it.
