I admit to being critical with the kit lens based on pixel peeping - it's like I want the image to be super sharp even if I don't 'need' it (I guess the way a hot rodder "needs" a car to go 200 mph even though the speed limits are 70).' I'm not rich or poor, but do have a bad habit of spending more on things than I should to get 'the bests' even if I don't need it, while not saving enough. I'm trying to break the habit. Not doing good.
Yeah, I am the same way. I want my images tack sharp too. Just keep in mind that the lens is only one piece of the "whole picture". Getting a more expensive lens does not automatically make your photos appear sharper.
Another thing is that for capturing good shots from my understanding especially telephoto or 'dusk' type settings, speed is important? Is there really a big difference between, say, a 3.6 ap versus 2.8, or 1.8? For the non-pro of course.
Yes, there is a big difference. Going from 1.8 to 3.5 effectively halves the light that makes it to the sensor.
Going from a f4 to a f2.8 telephoto lens also makes a huge impact on wallet, size and weight. So YOU have to decide if you NEED that 2.8 (a professional sports photog sure does), or if 4 is sufficient for you. That 2.8 at dusk might still be as hopeless as the 4. Know what I mean?
The other thing with aperture, as it opens up you lose depth of field, which becomes awfully narrow with a tele at 2.8, which means your object better not be very 3 dimensional and your focus is spot on. Just for that reason, you will find yourself use mid range apertures much more often than the extremes. Of course, it is nice to have, just like the ability to go 200 mph. But is it worth it to you?
I am NOT trying to talk you out of your L lens collection.
Best thing would be to borrow a couple of lenses and see for yourself.