On Screen Action?

So, I've been thinking quite a bit recently about how often I get the remark, "Where's the on screen action?"

To be honest, it's not that I don't write it, because I have, it's that the books I've published so far are ones where I believed the "on screen" action to be unnecessary for character development, plot, et al.

Right now, however, I'm working on something which most definitely requires on screen action because of the nature of both characters and because it's a plot point.

I'm just a tad hesitant about it though and was wondering if anyone would be willing to beta this one. I don't want to go overboard, but I definitely want it to be--honest.

Quick story summary:
Dyre is one of the Faithless, a holyman who lost his faith so utterly he became unable to touch holy objects, holy water burns--even the touch of someone who has faith can burn. Isaiah is one of the faithful, an Inquisitor who was put in charge of Dyre after recruiting him to take up the cursed sword Vloek, a weapon which can kill demons. The two have worked together for three years, but lately, Isaiah has been acting strangely--little glances, strange proclamations--touches. It's enough to drive a man crazy, and Dyre's getting suspicious. Has Isaiah changed his mind about Dyre, or has Dyre been wrong about the Inquisitor's motivations all along? 

I'm also kind of curious as to how everyone else makes the decision to do on screen/off screen or fade to black and what leads you to that decision. As for readers, what is your preference?