Yo good practice man. Any pace that works for you is a good pace, so no worries about finising earlier or later.
As for feedbackt there are a couiple of points that come to mind as I see the lineart faces.
There seems to be a bit of... say, inestability in the lines, not the little ones, since it makes sense to work small lines with the wrist, but the longer lines that define the outlines and main parts. If you haven't try to use the elbow/arm to do those long stretches, even if you overshoot, you will still have cleaner lines wih a nice smooth at the end, and then you can erase the excess.
For the little details, I'd recommend to try to put some more emphasis on the line weight used. There IS some weight applied, but for the most part it could be used more to put more attention on volume.
The last one has to do a bit more with style and is very subjective. It seems you enjoy sketching out little details with different line forms, and if this is your preference, that's perfectly fine. For arts, refining a style might be better than refining technique, it all depends on where you are heading. However, it's hard to tell some details, like the necklece or nose forms. The lips overall look good, but the beard looks like a bit of squibbling with no clear direction of the beard form. And as I said, if this is a style choice and you enjoy it, by all means, maybe it's just refining it a bit more. If we're talking about tech, it would make more sense to have the lines follow the overall shape of the volume.
Here's a small example:
Regardless of preference, I do think it's worth trying the different styles that exist out there, and then come back and stick to the one you prefer.
