While there is nothing preventing her from doing so, Taylor does not seem interested in pure weapons development. Instead, she would continue to develop the basic science needed to let others implement the weapons tech needed to equalize things.
Also, keep in mind that Taylor is learning from extraterrestrial broadcasts, the nature of which do not match the known alien races from either setting, making it unlikely that she is in either of their worlds to begin with. As such, she in unlikely to become sufficiently invested in those settings to spend much of her time worrying about them. Particularly since, on a personal equipment level, she can already do as well for man-portable gear. (Space Marine tech does not count as man-portable, of course...)