That's lot of S's.
I like both of these.
I'd be careful though-- Sam is caricatured while Santa is very Tezuka esque-- those two styles don't completely go together. Don't get me wrong, it can be done, but it tends to look awkward like an episode of Drawn Together.
Let's look at some of Tezuka's faces...
All right so we can see that Tezuka San employed simple lines and shape for his face details, as displayed here. We have the button nose (bottom right) and the pig nose (bottom left) we also have noses with bridges and nostrils so the variety looks close to what you have.
The key will be to maintain the ink line, in your current pencil state, Sam has very sharp lines while Santa has soft lines-- if you make sure your ink line is consistent you should have no problem.
Sally's Page here.
It's rock solid all the way through except that it's 130 when he looks at the clock and it's 230 when he clocks out. Hmmm. I'd just adjust that hour hand.
The bottom panel being open like that might look odd, but I like the openness of it because the remaining panels are very cluttered (which in this case is not a bad thing).
Here's the biggest change I would make;
Compositionally in that top panel he's a little too close to the top for my liking. I did a focal point marker so we can see where the center of the panel is, anytime you have something of interest, of importance, it should be closer to that focal point, by moving everything behind the counter down a notch you make it a better composition.
Nice job Sally.