Great stuff! Huge fan of the first TW:W, I've been really digging all the 3d Models and art you guys have been releasing :) Pretty cool to have someone like you around I must say
It's interesting to hear another 3D modeller confirm that good line work is more important for them than anything else; there seems to be a predominant opinion in the online concept art communities that "realism" or photobashed concepts are whats needed and that lineart is a thing of the past. But i've spoken to a few other modellers and concept artists at my old job and they said the same thing you have said here!
Anyways, some places you might want to check out to get started (keep in mind I'm still learning myself!)
For drawing, Proko is a great resource:
https://www.youtube.com/channel/UClM2LuQ...23462tQzBg His free videos in my opinion are sufficient, but I've also bought most of his courses and the extra bits of explanation as well as extended critique videos are also helpful.
He has series on both anatomy and "how to draw" so to speak. You already have a good understanding of musculature and proportion from your 3D work, so you can maybe skip over those more textbook-like anatomy videos and follow the drawing ones, although there is some coverage on how they appear when drawn too but thats a minor point in those videos. I believe the course is called 'Figure drawing fundamentals' and will cover gesture, lines, curves etc rather than muscles and such.
Right now its a question of transferring your 3d knowledge to a 2d plane, and step one would be gaining more confidence in your lines. I understand these are quick <3min drawings, but its good to practice drawing with fewer marks. The drawings themselves seem solid, but the lines are a bit scratchy and uncertain. I think part of this might be that youre trying to capture in your drawing more than you're capable of in that time frame; so i'd recommended reducing the amount of detail you're seeing/trying to draw in these shorter studies. For example, how these figures are simplified in a 2 min gesture:
https://www.youtube.com/watch?v=0I_egPHop9A
The figure still shows through and reads very well, but the emphasis for most of the drawing is not on the bumps of the arms lets say but on the flow of them. Save the contours and anatomical bumps for longer drawings!
Other resources might be any of these books:
Bridgman or any of his other books:
https://www.amazon.ca/Bridgmans-Complete...1402766785
Any of Loomis' books:
https://www.google.ca/search?rlz=1C5CHFA...i0XJS-iIts
maybe optional, but going more in depth in perspective can help a lot even for characters and creatures. Note that the above Loomis books will cover basic perspective. Scott Robertson's How to Draw is the single best resource for perspective, but is mainly geared towards vehicles or environments rather than characters:
https://www.amazon.com/How-Draw-sketchin...bc?ie=UTF8
As for Line art, one of my favourite artists and line artists happens to work at Creative assembly too, maybe you can give her a visit (I'm assuming youre both working in-house, i have no idea really lol)
She's also a phenomenally good designer, someone i look up to personally as an artist and designer:
https://www.artstation.com/bethh
As for design, theres no real answer to this. It's largely personal taste. There are vague concepts that can be explained, but even those can be broken and often are. With that said, silhouettes are probably the only thing I can really point to as a steadfast rule. Not just the silhouette of the character as a whole, but the silhouettes of the objects they're wearing and how they relate to each other. Let's take one of the images youve posted as an example:
The size, shape and value(on the grayscale) of these elements relate nicely to each other. We have varying amounts of each with the gambeson being both the largest piece of physical clothing and the single dominant colour proportinally, with secondary accents in the armour, and tertiary accents in the yellow belt, trim and collar.
Balancing these two levels of silhouettes is in my opinion the only universal principle in good design. Besides that, even though you don't necessarily need to "Draw" any of the below, you will have these other things to consider depending on what you want to achieve visually. One good reason to have a rendered character is to see that these design elements will actually work when everything is lit, as something can sound good on paper and in line but look awful when its animated, modelled or lit:
Colour palette (This will partially be determined by your silhouettes above and some elements below. For example, if you have made a design with a lot of small detailed elements of varying materials, theres a chance your colour palette could suffer as a result. You might have a lot of competing colours as a result. So, your palette should also follow good design similarly to the silhouette example above; think of one dominant colour or hue with 2 or 3 secondary ones to accent and complement the main one)
Material variety (examples: placing metal beside fabric, layering types or colours of fabric, using one kind of material exclusively vs multiple types etc),
clothing construction (types of seams, buttons, patterns and embroideries; how clothing is made using those different elements; thinking about why a specific material might be used in a specific spot or on certain kinds of design etc)
Historicity, culture and practicality ( how historically/culturally based is your design? how practical would it be to actual use? Does that matter for your design or is your only goal something new and unique?)
Character posture and expression. It can be important to distinguish characters not just by their clothing or items they have, but how they stand, compose themselves, or interact with other characters (potentially) (In Disney animations for example, this often takes precedence over some of the above elements. This is less important in video games more often than not, or only really takes importance when its being animated in some form)
Theme (If your design is part of a larger body, do they work well together? Do characters of the same region/faction etc feel cohesive?)
Uniqueness or identifiers (Some characters might have a feature, item or piece of clothing that distinguishes them from everyone else in a universe and is unique to them. You can see this a lot in hero-type characters. Other characters might have an identifier that shows they're part of a certain group, like an emblem or specific weapon type)
Story related (If you're working on something that ties into a plotline, consider where the character is in that particular moment of the story, and how this might be reflected in their design. For example, In starwars, the change in luke's clothing from the first film to the last)
And possibly a bunch of other things I'm forgetting :) But that should be a good starting point. From here, find images of things you like, do a study of said thing and take notes on what you think is going on with the design or what you like about it, keeping those points above in mind. It can be a real object like a historical armour, or a design for a game or movie that you like and think is succesfull, or literally anything else. Even trees, bones, or other random things in nature can have good design that you can pull from!
Cheers and can't wait to see what you do next