Average stack vs. 2 huge stacks LAGGs

1/2 and I'm sitting on ~140 bbs. LAGGs have ~ 400 and 600 bbs.
I ended up playing a short stack strategy against them when oop.
Limp re-raise AA, KK, and AKs. CR overbet flop with set on slightly wet board.

It sucks losing so much value. But against huge stacks with wide ranges who play well postflop, I feel like protecting my stack is paramount.
Besides that, showing that I'm willing to get my stack in slows them down enough to a.) open my game when I'm in pots with them in position; and b.) get them out of my way and playing pots with the rest of the fish.

It did feel like I was playing a little scared though. Thoughts?

You're playing for 150bb - their stack size is irrelevant unless they're shorter.
I don't understand the question really. You do whatever is profitable.
I don't understand what "Protecting your stack" is supposed to mean.