Such (as I say "guardless") look is common not only for those undergoing medical treatment, but also for anyone who is feeling lost and perplexed, even if feeling well and healthy.
What helps in supporting one's exterior in this case is what normally appertains to someone who is focused and level-headed (as opposed to confused) - something we tend to take for granted as long as everything is alright.

A shaved head or the fluff growing back after chemo can surely look quite pathetic, can't argue about that.

Sometimes it just happens because of an unclear or somewhat awkward SHAPE of what has grown (or of the skull itself), sometimes because of the LOSS of natural CONTRAST (both are easily fixable, and below I'll explain how-to in more detail, but first let me finish with the rest).

So, next one. Clothes.
A shaved head instantly makes one's image more graphic.
And the GRAPHICS, as well as the CONTRAST that I've mentioned above, has to be supported, especially if the head remains naked
(more on that below).

So, look. Just two points (head shape and outfit contrast), but the task is almost solved once you've dealt with these two.

(Can't give you no pictures, though - I've got none of my own and I can't use someone else's (will be great if someone can send me theirs, I'll add some), so I'll just describe it all in words)

So what will be good then, undoubtedly and at all times?

...well, this is more difficult and I can't name something just like that… Whatever comes to mind, comes with certain limitations - depending on the age… depending on the character… depending on the body type...

There's just one magic pill I think I can name though, which is makeup.
Brows in particular. Brows are our everything. Many treat them as the last thing in makeup, while they're actually our face. They draw attention much more than the mouth or the eyes. The latter two are more about sexuality and femininity (which are different), while the brows speak about your state of mind. You don't paint them like eyes or mouth. You just bring them back to their natural state. Without changing the shape or trying to intensify the color. Just put them back on your face, that's it.

And about smiles.

Hardly ever do we look so pathetic as when we give that forced smile. Ages have passed since the times when "smile whatever happens" was considered good advice. I believe it has ceased to be trendy for all cases except one: if you have noticed that smiling truly makes you feel relieved. I strongly suspect that that's a typical case for the Good Old Guys and the Innocent, but can't say the same about the rest, especially those who ideally look stronger and more attractive with a smile absent.

Have you noticed that a smile doesn't become everyone and there are people that look even more attractive when their face is serious, sad or even aggressive? Attractive here means "the one that draws attention, catches the eye and is suggestive".

Talking about the archetypes: smiling definitely goes well with the Innocent and the Good Old Guy; also the Lover, the Jester, the Creator, the Explorer, the Caregiver and partly the Sage, but their smiles are very different from each other and are nothing like those of the Innocent and the GOG.

The Heros, the Outlaws, the Rulers and the Magicians look way more interesting without a smile.