Using a gag series to practice writing

I'm soon starting my webcomic. Unlike most webcomics - which are mostly comic stripes - mine will be more similar to real comics/manga. Mostly it's parodistic or statiric, like South Park (alrought I don't want to be as anvilicious as they're). But amongside to doing it for fun (gags are randomly popping out of my mind, eg. I mixed No Smoking with the controversy of tobacco control in Hungary) I also want to practice writing. It'll feature some fight scenes (sometimes in vein of affectionate parodies), so I can practice to coerographing them. Also it'll good for my art skills, it seems I learn faster than others (now my art has depth, and if I draw other's characters they don't end up as originals).

But what about the rest? I also sitting on a "masterpiece", that still need writing, and that's even more important for me.

Seems like you've already made a few points in the webcomic's favor. If you think it's something that'll help you — or just something that would help get your name out there — then by all means go for it.

I'll tell you one thing, though: working on a gag story can help develop a different style from your masterpiece, and you can use that as a reference point in the future. If you develop one type of humor in the comic, you can gain a better understanding of how to differentiate that from the humor in the masterpiece. Same goes for plenty of other elements, big and small. Characters, ideas, settings — and I'd like to think that's doubly the case if you're working in different mediums. (Though the reverse is probably also true; certain skills and learned techniques might not carry over.)

Conversely, maybe making a gag series can help you out by helping you develop a certain style, and then integrating that style into the masterpiece. Maybe you find out that you have a talent for making random gags (or just really enjoy doing it), so you can bring that talent into the masterpiece as needed. Or — even if your masterpiece is a bit more serious — you can take the wit needed to make your parodies and inject that into the dialogue/opinions of characters.

I'd assume there are a lot of benefits to taking on projects of a different style, and I'm hoping that whatever you decide to work on, it works out for you. Just go with what you think takes top priority; if you feel like your masterpiece is more important, develop your skills using that instead. If not — OR if you think you can handle both at once — then go with the gag series.

Whatever the case, good luck on your end. Hope I helped you out a bit.