Great work, Mr. T1ckle. I didn't understand what's these characters will be used for. But do you intend to detail them? They are looking very good.
About the walk cycle, it's good, but it could be real better. I'm not felling the weight of your char. You see, walk is falling all the time. You fall, but put your leg on ground, recorver balance. You fall again, put your leg on ground, recorver balance. And it's this, all the time. It's not well defined where your char fall, recover balance, stretch, and fall again. I think this link would be useful for you:
https://www.idleworm.com/how/anm/02w/walk1.shtml
This guy explain a lot about walk cycles. But if you want a byble of animation, I recommend Richard Williams book, "The Animator's Survival Kit". It's an incredible book about animation, to be applied in any media you want, including 3D.
I hope it helps!