dude, I think ur seriously over exaggerating the newborn's abilities. The newborn was NOT invincible to all weapons, it would have quite easily been killed with conventional firearms. It's skin was not chitinous armour like that of other xenomorphs, so, infact it would probably go down easier. Second of all, the newborn may have had greater physical strength than a standard drone, but this slight advantage was countered by alot of disadvantages. First of all, the newborn's movement was very sluggish, as a result, even the least fleet footed of other xenos could easily outmaneouver it, furthermore, it was stripped of an aliens most crucial weapons, it's inner jaws & it's tail. This means the newborn would have a significant disadvantage in battle.
Furthermore, on ur comment of a newborn being able to take down a queen, I don't think so. The only reason why the newborn killed her in resurrection was because she was still recovering from giving birth & barely able to move, ontop of this, I doubt she was expecting her own offspring to take a swing at her. If it had been an actual toe to toe fight, the newborn would have been torn to ribbons in seconds. Realistically, how would a slow-moving, albino abomination be able to take on a 15 foot tall killing machine who would be more than a match for a t-rex? The newborn was not a super-powered beast, merely a freak, & as I have already stated, a major disgrace to the franchise.