Do you want to use more then one light at a time? Do you want control over percentages of natural vs. flash? Do you want to easily dial in exposure in just one or two shots? Sekonic L-358 is the answer. I got mine used for $200.
Best $ I've spent on camera gear. ( these are MY opinions)
Hopefully you are not confusing manual camera settings with AF (auto-focus) settings on the camera, as the latter have nothing to do exposure and light metering.
That said:
Once Upon A Time......
Oh, back about 1968 or so.......
When nearly all photographs were taken one (1) shot at a time, very deliberately, and in-camera light meters were poor to average and slide film could record only about 5 (maybe 7 if everything was perfectly done) f-stops worth of contrast......
I used a light meter all the time.
The question is this: Is that how you are shooting with your camera today? One shot at a time, very deliberately, everything set up ahead of time or very static scenes? If so, you might find a really good recording and averaging light meter that shows high and low exposures and zone ranges to be useful to your work.
If you are playing with multiple light setups in non-balanced or non-TTL operations, using manual camera operations, as pokemanyz mentions above, one could be handy after you learn to use it. But don't expect to ever get things done rapidly. Check out "Strobist" for a lot of help in this regard.
But, as I write this my second screen is displaying a bumblebee on a thistle shot with a 6 flash macro rig, in manual (set up for hummingbirds). It was far faster to set it up, shoot a couple of test exposures and review them, then adjust the lighting ratios manually and reshoot, than it would have been to set up and shoot in each flash, measuring it individually with a light meter and then going back and re-re-setting the ratios. The tools available in the camera today are, to my mind, all that anyone needs in order to do really outstanding work.
Not quite sure what your definition of "gratifying" is but I use film mostly and two of my Leicas have excellent meters in them that I often use. However I mostly use a Gossen Digipro F so that I can read incident light levels.
