I have never used a camera-brand speedlight and incorporate with its auto sync functions; so I can't say how useful they are.
Even in the old days(80s) when I had a Nikon FM2 and a Nikon flash, I didn't know its full usefulness. Then I bought a Sunpak which at least I could rotate its head up and down, plus used its close/zoom features.
Not too long ago, I bought an older Pentax flash which I found had less power and drained the battery much faster. Still I didn't know how to use its functions with my then Pentax camera except pushing the slider according to the approximate distance. It could not represent a true camera-brand flash because it was built for the film era.
I had 2 Yongnuo flashes(one with a dial and one with digital-step adjustment) and I liked its intensity step adjustment plus up/down and rotate features with built in diffuser and reflector attachments; but its battery compartment door could not hold up in position. But at least it can fire 100 flashes per charge.
Now I have the Neewer which are a bit bigger but with more power and about the same price and features as Yongnuo; it can fire over 150 flashes easily per charge.
I want to know if I missed anything wonderful about a camera-brand speedlight to justify its cost over usefulness.

thanks CO,
Neewer has no TTL, but adjustments of intensity by small steps; I find this Neewer is better than my old Yongnuo which the battery door was flimsy that I need a strong rubber band to secure; it has a master/slave mode, and can be attached to a remote hotshoe.
This Neewer model won't communicate with the camera. I am sure some other expensive models can, but how about if I want the background be half lightened? In my case, it will be all manual by trial and experience.

thanks CO,
Neewer has no TTL, but adjustments of intensity by small steps; I find this Neewer is better than my old Yongnuo which the battery door was flimsy that I need a strong rubber band to secure; it has a master/slave mode, and can be attached to a remote hotshoe.
This Neewer model won't communicate with the camera. I am sure some other expensive models can, but how about if I want the background be half lightened? In my case, it will be all manual by trial and experience.

I know many of you use the flash made by the same brand as your camera; but I am too cheap to spend over $200 for a flash light.
My gear is Nikon D610($1100 new) with my favorite newly acquired($170 used)Nikkor 24-85 3.5-4.5G ED
I use a Neewer TT660ii flash($45 new) which I can manually and rapidly change the intensity by taking a couple of test shots.
I use it mostly on portrait with background, firstly manually set my camera on the background, and then adjust the brightness a couple of steps down using the [+/-]button, and then supplement the lighting to the portrait with manually setting the flash light.
I don't if this is a common practice, please comment .

I opt at smaller screen provided it has enough RAM for PS to operate fast.
There is a big difference in weight between 11" & 17".
I am 65 and use a 40" monitor at home with my desktop and an 11" laptop to travel;
plus a 1T Seagate external HD to store all your pictures and another one to backup.

thanks, of course, there are many ways to overexpose a picture by steps, so are you trying to say, overexpose will create less noise and more details than underexpose of the end result?

Thanks Todd, you got me a little more confused now.
I shoot mostly with ISO on auto and then adjust with the +/- button.
In such case, let say, when I point to the brightest area, it registers 200 on auto, then I change the ISO manually to
100-L50 (will result in underexposed) or to 250-350(overexposed).
If you can clarify this, that will light up my bulb.

where can I find the Color Checker tool?

Now I got a little confused, did you meant
1. use spot meter (single) focus
2. point the red-square (focus point) to the brightest area of the subject
3. then press on the AE/AL button and reframe
3. increase the aperture by 2 to 2.5 stop; what happens if the aperture is already large enough?
3a: can I use the =/- button to the + side then
4. take the picture
Did I get that right?

thanks, I always think the other way, underexposed is better as I think the shadow slider works better than the highlight.
I will try my brightness indicating in the middle, and when in doubt then add a few points with my +/- button

For my limited understanding, if the LCD display has clippings(flashing some highlights or dark areas), that means some information in the picture are not captured even in the raw files. Otherwise, the picture is considered OK with all the details?

how about my other 2 questions: any comments?
Should LR be sufficient that the output jpg need no further process (levels,color, contrast, brightness, etc) in PS?
I thinks the answer of the first question is Yes, unless the raw file is deleted.

If one hesitates of the exposure during shooting, underexposed is better than overexposed Or the same, (of course by the same amount) ?

Nikon raw file .NEF is different from the others DNG, which can be viewed in Faststone. I am not sure NEF is a true presentation of the raw images? But I think the NEF files is afftected by the White Balances of the camera setting. Am I right?

I shoot raw mostly along with a jpg version for backup and comparison; the jpg output from LR should look better than the jpg created by my D610.
Can anyone tell me setting the WB of my camera makes any significance to the Raw files; Will the Temp & Tint slider of the LR over rule all the camera WB setting ?
Should LR be sufficient that the output jpg need no further process (levels,color, contrast, brightness, etc) in PS?
If one hesitates of the exposure during shooting, underexposed is better than overexposed Or the same, (of course by the same amount) ?

when I switched from cropped to FF, I have more keepers. Could it be the technique that I improve or the equipment