...and an image of a 2017 comic -

I just took a look at your link to (I assume) your latest book. Right off the bat, I can say your 3D work is getting better. I think your earlier 3D work looked stiff (sorry). Believe me, I know how hard it is to get 3D characters in stills to look natural. So kudos there. Keep fine tuning your style. I see improvements, and you still have areas to build on, but good job overall.

Your hands are good in some ares and not as good in others. In my opinion more time should be spent making the hands look natural and not stiff. I know...I know....easy for me to say, but I think it is a constructive observation. I'd argue hands are the most important body part to get right in terms of body language and posing.

I don't know if your 3D app is strong with morph targets for the facial expressions but I'd build a bigger facial library and work in more facial expressions if possible. 

As for the dialoge balloons. Again I think you're doing a much better job in this book than in past books. but here are a couple observations I've made.

As much as I thought I was ok trying out grey text for whispering, I don't think it comes across that well, as is. It could be that the body language of the character at the time they are whispering doesn't indicate they are whispering. So grey text might work if the body language reinforces that action. Just a thought.

Having the same font size gets kinda boring. So I'd look at any letterer you may be a fan of and see how they add stresses to the dialogue. Mixing it up will go along way of breaking the monotony.

For the dialog balloons themselves, I don't think your squared balloons are "wrong" but they don't feel "right" either. What I mean by that is: Even though you are portraying a futuristic story, or at least a high-tech story, IMO your character's conversations and thusly your characters should always feel organic (unless they are androids, robots, etc). I think the rounded dialog balloons go a long way in make the dialog feel more organic.

 I also think one technical reason the traditional dialog balloons are rounded is to encapsulate the dialog more tightly and efficiently leaving little wasted space. Squared dialog balloons typically waste small amounts of space in every corner. Not a big deal perhaps, but something to be aware of. It's those little details that make good designs into great designs.

In regards to fonts being all caps. Again, I think there is a pretty strong technical reason to go with all caps - the letter forms are more open in caps than in the typical lower case letters. Meaning there is more white space for each letter so you can clearly see what each letter is. When you use lower case letters, I see areas where the letters are blending together. This is more an artifact of screen resolutions, but it's a real visual challenge that should be considered, tweaked and optimized.

To sum up, I gave my opinions because I really like where your style is going and I'm impressed by your improvements. If I didn't care for your 3d style, I just wouldn't voice my opinion here. I think you still have areas of improvement, but I also know you've taken on a big challenge going with 3D stills. If you can get your characters looking more natural and less stiff, I think you'll find more and more readers interested in your stories.

ok, I'm getting off my soapbox now.