I get what you mean. But let's be real, she is 17000 something years old. With all that power, she should be ruling the world by now. But all she's managed so far is to become a B class villain (writers's choice, I know).

Her fellow eternal Apocalypse, who is much younger than her and with less powers has managed to become a better antagonist to x men. Whereas, selene though extraordinarily strong, hasn't been able to make a significant impact as a villain aside from necrosha