I assume screen is a massive drain; starting with Apple's "Retina" push, and all manufacturers following, my tiny phone now has resolution and refresh WAY higher than anything I deem functionally useful (though I do have a friend or two that will incessantly talk to me about how "smooooth" scrolling or whatever is; don't care!).

As well, while on my original HTC G1 I optimized the thing to an inch of its existence, with modern phone there is SO much happening in background, I don't even know where to start so I give up and have literally bought couple of 10-packs of charger wires, and have wireless charging pods in several rooms.

I miss the days of my Palm Treo, when I could take it on a vacation and not bother with charger :P