As a mouse user, when my stick is standing straight i'm having quite the trouble doing it.
I'm not talking about pure line tool animation. It's only for the legs, and for when it's tough.
Btw I found no other place to post this, so.. yeah.

I often have trouble when my stick is standing straight as well.

Also there's an entire help section this could of gone in.

And to answer your question it's okay to animate however you want to animate. Whatever works for you is what you should do.

It'll look pretty goofy if you do half line half brush. Why not try just using line?
But you're free to do whatever you want, there's no real right or wrong when it comes to your style of doing things.

Like Charry said, you might just want to use the line tool for the whole stickfigure,
it's way to easy to tell the difference between a line stickfigure and a brush stickfigure

Quote from Veir

Also there's an entire help section this could of gone in.

Ya know, people dont check that section much, I've seen a post (like this one) get answered instantly in general,
and about 4-5 different posts in help sectiontake about 3 days to get answered, for example mine wasn't answered instantly
(*cough*pls answer my post*cough*)

i remember having this problem too actually

you're gonna want to get past that weakness at some point, so just keep working on it & practicing rather than cheesing it. do you really want to be that restricted forever? i'd say you should also buy a tablet if you're serious about animating anyway

i mean it's animation do what ever the fuck you want there is no "okay" way to do things. just don't make it shit.