Regarding the latest piece, your vectoring is really getting a lot better! The detail on the jackets is pretty darn good! The only thing I would mention is the hair, where there isn't actually any shading. I realise it is probably the hardest thing to do in vectors, but given the two hair styles you've got in that piece, this is probably a your easiest chance to give it a go! Also, I'm not sure if you've intended for them to have their eyes closed, or not to have eyes at all, just because the line where the eye lids would meet is really light and probably not dark enough.
Lastly, the text has a lot of room for improvement. I realise the main feature is the vector work, but if your text is going to cover up such a large portion of the canvas, you might as well get it looking really polished. First of all, it all feels very messy. Partly because it is not aligned properly, there are more blank pixels above the text than under it, it all needs to be moved up a fraction.
Also, under the word 'never', you've got a substantially larger gap until the next line that all the other words and it throws off the balance and makes it feel disjointed and separate. Also, the font itself is not bad, but it is a little boring. You could find a font that has a little more oomph, which would make it feel a little fuller!
Hope that's ok, but you are improving heaps! So keep it up!
