Unsurprisingly, I am in favor of directors doing some in-engine work on their projects. Confirmation bias is heavily at work here because I've done direct implementation on all of the games I've directed.
On F:NV I wrote* Arcade, Hanlon, Joshua Graham, and other characters in our editor. I also implemented and tuned all of the weapons and mods (and other system design things like perks and recipes) in the GECK.
On Pillars of Eternity, I wrote Pallegina and a few minor characters in OEI Tools. I did direct in (Unity) editor implementation and tuning of many spells and items (though Tim Cain implemented much of the code that I used). I also did some encounter work in editor.
On Deadfire, I wrote Pallegina, Eothas, and a few other convos in OEI Tools. I did less in-engine system work because I had a small team of system designers and I had more director responsibilities, but I did do some tweaking and tuning in the game data editor (GDE) of OEI Tools.
On Pentiment I wrote around 1/4 to 1/3 of the dialogue in OEI Tools and set up all of our dialogue checks in the GDE. I mostly stayed out of Unity because Matthew Loyola and Alec Frey handled most of the design tasks there. On Pentiment I did a far greater percentage of content work than I normally would, but it was also a team of 13 people with only 3 writers (including me) at any given time.
Here's what I think the "pros" are: you have a better understanding of the pipelines people are using, you are doing work under (mostly) the same conditions as the people you are leading. You are directly touching the data that is going into the game and it makes you acutely aware of what's involved in doing that (at least in part).
The cons are the obvious ones: your main job is leading people and if your nose is buried in the weeds, that can be difficult to do. Also when it comes time to cut content, you might get precious about the work you've done vs. the work other people have done.
In my experience, the important thing is to not overcommit. Do a little work, sure, but err on the side of a light load. It's not practical for you to even have a quarter of the content workload as someone working on the staff.
*Minor note but when I say, "wrote" that also includes any related scripting done within dialogue for checks, setting global variables, etc. All Obsidian narrative designers are expected to do the scripting for their dialogues, though the interface in OEI Tools makes that generally pretty painless.