Can't imagine what it will become if that's a combine DNA of all Gensokyo.
Then let's itemize it, shall we?
For starters, Cell will have double immortality thanks to Kaguya and Mokou. He'll be able to read both the conscious and subconscious minds of people thanks to Satori and Koishi (and probably be able to turn them off if he wants to). He'll have supergenius level intellect thanks to Eirin and Nitori. He'll be able to inflict both instant death and instant destruction just by thinking about it thanks to Yuyuko and Flandre. And he'll also be able to become completely invulnerable to damage at will thanks to Reimu. Oh, and thanks to Kanako and Suwako, he'll be a god. You can't see him at all thanks to Mystia and Rumia's powers. On top of all that, he's got just about every elemental power under the sun. In fact, he's got the sun, too, thanks to Utsuho's powers.
Oh, and if you think you're somehow winning against him, SUPRISE! You're losing again because he's got Kogasa's powers. Even if you're fated to win against him, he can still beat you because he's got Remilia's powers and he can change your fate. And you'd better hope you can sneak up on him and take him out in one hit, because otherwise he'll just use Sakuya's powers to stop time and kill you until you are dead. And if you do find a way to take him out in one hit, you'd better hope that it's guaranteed, since thanks to Tewi's powers, he's super lucky.
In short, a monster far more overpowered than anything ever imagined. Odds are though, since nobody in Gensokyo is actually evil, Cell might end up being a good guy. We can only hope.
Genetic doesn't work like that And if it DOES work like that, he would have only about less than 1/160 their power
In DBZ alone, Cell could use both the Kamehameha and Instant Transmission just as well as Goku just because he had some of Goku's cells. Cell has the regeneration of a Namekian because of Piccolo, and Frieza's Death Beam. In short, yes, genetics doesn't work like that, but this style of genetics is in line with what Cell normally does with other being's genetics.
