Good points, but I root and install custom ROM's on my Android phones, to get a smoother / faster experience, as well as much increased and better battery life due to the custom Kernels, and all the extra functions the custom ROM's add beyond the stock phone itself, as well as debloating the million apps I don't want or need.
Saying all of that, I do that within the first week of owning a brand new phone, and then I tweak it and setup to the way I like, and then never touch the custom settings again, and I will keep my phone that same way for many months afterwards, once it's all setup, I just use the phone regularly from there.
Same with the iPhone. My first new iPhone in five years was the 6 Plus I bought last winter, I Jailbreaked it the second day I owned it, learned all about the JB community, and tweaked the hell out of that 6 Plus, and then I liked the phone a lot better. But that didn't last 30 days before I returned it for a Nexus 6