Minutemen are your failsafe: if you end up in war with the Institute, you blow them up with Minutemen. If you end up at war with BoS, you can blow them up as well (only after blowing up the Institute though).
If you are mom on the quest to find (and protect) your kid, you gotta be a momma bear. And few creatures are as merciless as a mother protecting her kid.
If you want to make it easier, you can progress through BoS or RR questline. BoS questline will enable you to kinda roleplay getting to late to save the RR. If you go through RR route, you will come to the point where the RR decide to betray their Institute ally by deciding to save Synths even if it means causing countless human and synth deaths (including kids and other innocents), giving you a reason to stop them.
Funny thing is, by making the NCR lose you destroy the militaristic party which was bringing the NCR to ruin and wasting many NCR lives, not to mention you force them to stay home and thus restore order in their own lands.
So arguably beating NCR is good for NCR.
You only save some lives. Patriot's own family does not seem to have made it, and those guys are both good people and supportive of Synth freedom.