Going to stick with Scapular shrugs for a while.

I think this exercise is very beneficial to train the Serratus Anterior if done correctly. 

I am doing these with my toes pointed out ( similar like in a planche lean ) And I feel the Serratus Anterior more and note that the exercise gets harder if doing like that. 

Is it ok if i do them like this ?

And after mastery I am going to keep doing them as a warmup / prep exercise for the more advanced stuff.

For the scap shrugs, are our shoulders supposed to remain completely depressed (this would activate the serratus anterior the most, right?)? It looks like in the video the guy isn't focusing on too much depression and is instead just pushing his shoulders as hollow possible. 

Sam Carr said:

For the scap shrugs, are our shoulders supposed to remain completely depressed (this would activate the serratus anterior the most, right?)? It looks like in the video the guy isn't focusing on too much depression and is instead just pushing his shoulders as hollow possible. 

I'm not sure if 'depressed' is quite the right cue here, or not.  Personally, if I depress the shoulders too much, I start to get all sorts of clicky impingement-feeling sensations.  I do try to keep squeezing my scapulae against my back, though.