It's okay to toss in actions. Just don't get into elaborate detail. As an actor who has worked in several film/tv/industrials, I would not be offended by general additions like you described. It helps me to make sense of the character's motivations. Sometimes dialogue isn't enough. As a director, do yourself and the actor a favor, don't make it a game of mindreading.
Most indie filmmakers will start by working with non-union talent who they aren't even paying or paying minimally/deferred. I've worked with some awesome talent who are non union. As a director, writer and actor, I don't put up with prima donnas. If you're hiring an actor/actress simply for name value, you need to decide beforehand if you want to put up with ego during the audition. Casting is often a very important decision but not one to be discussed here. I've been fortunate to work with some name talent who are remarkably grounded.
As a writer, your goal is to create context that the director and actor can work from that isn't overly restrictive.
Bland script:
Code:
Jim looks at Todd holding the gun.
JIM
She still loves you.
Emotionally enhanced script:
Code:
Jim[COLOR="green"] smiles[/COLOR] and looks at Todd who holds the gun
[COLOR="green"]and fights back a tear[/COLOR].
JIM
She still loves you.
This gives the actors some sense of the internal states and lets them develop some internal backstory. If an actor has a problem with a script, it's okay to get the thoughts. As an actor, we invest time in preparing. However, as a director, it's your call. It's possible to be respectful and work with the actor to get the expression you're seeking in a scene.
What would I consider overkill writing for me as an actor?
OVERKILL:
Code:
Jim raises his eyebrow, shakes his head and
smiles, curling his lip. He looks at Todd who
holds the gun. It shakes as it waves at Jim.
His chest heaves as he fights back a tear.
JIM
She still loves you.
In this case, you're telling me how to act. How I portray "smug" needs to be authentic to me and the character for continuity. Similarly the range of emotions inside Todd can't be captured well on paper, so telling me how to portray that is pointless. Hope that helps from the writer/actor perspective. Good Luck.