The thing to keep in mind about dithering is that is tends to create the illusion of a rough texture, and when pixelling things like metal and skin and other, similarly smooth surfaces, it generally something to avoid. That said, I think the dithering works quite well here for a few reasons. First, the contrast between shades isn't super harsh here, and as such, the image retains a pretty smooth, soft look. Second, I'm no tank expert, butfrom what I've seen they aren't generally made of super-slick, shiny, smooth metals; their surfaces usually appear rather matte, flat. Lastly, this is just personal oppinion, but... I mean, tanks'd take quite a beating in the field, don't they? Honestly, I don't they should have that "super shiny clean and new" look, anyway...

Apologies for rambling. I'm not thinking so great atm. I think the new one is a pretty vast improvement over the previous, which was better than the first, so... good pattern there. Keep it up.

Right off the bat I'd say you need much higher contrast. At 1x zoom, it's basically impossible to tell that these are shaded. I would use a softer color for the outlines, too (as people generally seem to frown on straight black).

These suffer from the same issue as many other RPG sprites, too. Given that these are (I'm guessing) meant to be top down sprites, the perspective is a bit off. At the moment they appear to be staring straight at the viewer/player/whatever. It's easily fixed (just lower the eyes a couple pixels and maybe extend the cranium one or two) but it's something that should be righted...

I like the gryphon and the twin doggies.

The first and last ones are simply fantastic, but I agree with filax about the second piece. I find it to be a bit hard to read overall, and in some places, the rapid colour changes give the appearance of, well... a mess, more than anything in my eyes. Honestly, my oppinion is pretty irrelevant here, never having worked within the boundaries of c64 restrictions, and admittedly being no where near your level in terms of artistic understanding or ability, but I sees what I sees. I'm pretty sure that, on the whole, the 'messiness' is probably a result of the restrictions, but it doesn't change how it looks, in the end. That said, I appreciate it from a stylistic/restriction-riddled point of view, and I do like the triangle stuff generally...

As for the others, well... like I said, they amaze me plain and simple. I love the limited use of the (already limited) palette in the first piece, and the last one is both technically and visually beautiful, far as I'm concerned (can't comment on likeness as I've never seen your for-real-face, but I'll give you the benefit of the doubt. ). As it usually happens when you or ptoing or any of the local powerhouses put out any c64 stuff, I'm inspired to try my hand at it. Maybe I actually will this time...

Overall, I really like 'em.

I just realized that instead of the 'insert image' tag, I used the 'bold' one in my first post... I gotta start getting more sleep... 

Either way, it's fixed now...