50mm 1.8 vs 1.4 lens?

I currently have a 50mm 1.8 on my Nikon D3200. What would the advantage to getting the 1.4 be? More bokeh?

Nothing really. You'd probably need a full frame camera to see any real benefit at f1.4. Various indications are that the f1.8 is a sharper lens anyway and has less distortion.

More light would reach the sensor in the same period of time if you set it to its maximum aperture.

"Bokeh" doesn't come in quantity it comes in quality.
Whether it is worth changing lenses for the difference in the out-of-focus parts of a small number of shots is really down to you and the sze of your bank account.
Personally I would say that from a bokeh point of view it isn't worth the money.

If you want significantly better bokeh I would recommend adding an 85mm f/1.8 to your armoury.

Even the Japanese can't explain, "Bokeh," and they invented it. The closest Western translation is, "Arty bullsh*t from people who don't understand depth-of-field."

That extra half stop will definitely affect your bank balance, but its effect on your photography would be negligible.

Bokeh is not about an out of focus background, but about the quality of the out of focus image.

It has sometimes been called "buttery" since the colours in the background run smoothly together.

Yes, prime lenses do have a better chance of producing good Bokeh, but the only way to tell is to actually attach various lenses to your camera and take some shots.

Generally the longer the lens and the more iris leaves a lens has, the better the chance of producing good Bokeh. Many lens makers also design the leaves of the lens iris to be curved which can enhance the look of the out of focus backgrounds.

I have an old, old Nikkor 105 mm f/2.5 lens which has only lens 5 elements in 4 groups. If I want buttery Bokeh, I attach this old lens on my Nikon D300 or D3

In general, the fewer elements, the better chance of the out of focus image will produce buttery "Bokeh" This is why lenses like the very popular 24-70 mm f/2.8 lens is not known for producing pleasing out of focus backgrounds. It has 15 elements in 11 groups. I know this is rather "techy", but these are the kinds of things you have to discover before you spend any money on a lens hoping for good Bokeh

Not much difference in the degree of out-of-focus blur, but the quality might be different, and you can only make a personal decision about which pleases you more after shooting pics with both lenses in various conditions and looking at the results.

Only make the change if you are really convinced that the change is worth the extra money. The angle of view of any 50mm lens is, of course, the same, as it would be of any zoom lens set to 50mm.

No-brainer.

But the lowest f/number you can afford.