“also”, not “only”, and then my answer is YES 
I like the smaller boards too, you learn other things there – which may help you later on 19x19. Fight, withstand, capture, try not to be captured … and sacrificing seems to have another flavor here.
“Should”? Well, at your current rank I’d say …
- Play as much as you can. (and humans, of course!)
- Study as much as you enjoy it.
Quoting EdLee on the L19 forum, in “How to play games?”, I recommend reading his whole comment there.
[quote=“EdLee”]About thinking time – another eternal question (browse other threads).
Don’t think too long (e.g. 3+ minutes on every move is too long.)
Don’t play with zero thinking (e.g. 3 seconds or less on every move is too fast.)[/quote]
Sounds like a very good advice to me. Note the italics.
See also here.
And @Kartigan, you forgot one point:
Tsumego! Tsumego! Tsumego!