Yes, lately I have been questioning whether going super wide is even necessary. I think a good player can definitely achieve very competitive victory times with 8-10 cities, because you will get your infrastructure up so much faster not having to invest thousands of hammers into settlers.. Personally I think going for your VC at T100 is too early on standard.
I have gotten the spaceport tech as early as T140 though, so realistically you can definitely go into tunnelvision mode at T120/T130. Whether or not building research labs is worth it is still a hotly debated issue, for example. But yes, I agree you barely notice the slower speed. Slower game speeds have so many advantages for the player it's insane. Going from Quick/Deity to Standard/Deity feels like playing on Emperor again!