What lens to purchase next

[Vinny]

While what you said is true the smaller focal length zooms can be handled by stepping a little back or forward. A 35mm or 50mm with a f stop of 1.8 is cheaper than a zoom with a f stop of 2.8 and a newbie may not get much out of a expensive lens at this point although I see that Tamaron puts out an inexpensive 17 - 50mm f 2.8.

Not sure how much better a zoom with a 2.8 maximum vs a 3.5 maximum (assuming you're shooting at the lowest focal length) will give you bokeh wize but it will be much more expensive than the 50mm 1.8. But first you need to know what you want the lens for.

You don't buy the 2.8 zooms for the aperture at the wide end - while half a stop is nice, it isn't that nice. It's for the mid and tele end - by 24mm you're already a stop ahead (2.8 vs 4) and at 50mm it's 2.8 vs 5.6. That's the deceptive thing about the kit zooms. It's rarely mentioned just how quickly the f stop shrinks (I assume because the aperture diameter maximum is near constant) as focal length increases.