Wow. Thank you so much for this post! I always thought I was flipping crazy, but it actually makes sense now!
As an aside, I just went ahead and bit the bullet and got a new laptop as I was under the impression the CPU was very power hungry, and that no matter what upgrades I gave it, it would never be "efficient" enough for me to use for what I need a laptop for, which is battery life.
Thank you for helping me understand the issue was always there, and that I should've definitely researched more before I bought these upgrades!