The takeaway would be "therefore everything she did was Right and Based because it empowered her bloodline"
Yeah, that is a worry. I'm trying to frame blood strength as morally neutral, but I'm not sure the fandom would read it that way if it was canonized. "Makes your team stronger" does tend to become "morally good" in the fanbase's mind. Especially since
actual noble accomplishments would have the same effect on blood strength.
...all it really gets across is that if you Go Out And Do Colonialism, your ingroup will profit massively and your descendants will become a breed apart, inherently superior to the unwashed masses they're brutally exploiting.
"What if the racial justifications for colonialism were just true" is a bad move, basically.
This, however, is just not accurate. Colonialism was not motivated by a belief in Lamarckian evolution; people weren't thinking that enslaving a bunch of people would increase the strength of their own genes. White people weren't worried that living an unexceptional life might reduce their children's chances of being white. They thought that they were already superior and would remain so as long as they didn't breed with their lessers.
In other words, their beliefs were a lot closer to the way it works in canon than to my proposal. And like I said before, under my proposal righteous heroism would also make your blood stronger. Important thing is to be powerful and impressive, for good or for ill.
Course, in Exalted the Dragonblooded actually are a breed apart, inherently superior to the masses they're brutally exploiting. And their ingroup really has profited massively from colonialism. So it's a bit hard to get away from that.
If your #1 priority is to avoid unfortunate implications, the best bet would almost certainly be to make blood strength a true mystery in-setting. People have theories, and some families seem clearly stronger, but nobody really knows what's going on.