the androids do not have unlimited ki. it would be a good way to make them original yet balanced, but several times in the show before they were going to fight trunks or gohan or whoever, you would hear them say that they didnt have the energy for a fight with super saiyajins. Or that their energy was running out or somehting. Im sure of this. Now i do think they should have more ki. Perhaps 5x like someone said earlier. And it should not be possible to recharge this. You run out, you die. So maybe 20x would be better. Also make their melee attacks do 1.5x damage, and they should be the fastest chars period. It doesnt matter that buu and cell was stronger then them in the show because how would that justify krillen being in the game? Im thinking not to many ki attacks, melee should be the main focus. Ah heres an idea. Since they are so similar. Just put one android in. With two models though. So when you start you have a random chance of getting either 17 or 18. That would be interesting.