Every image is different, but...
My workflow is generally LR -> Photoshop (which includes the Nik Collection) -> LR, and there are adjustments done in LR on both ends. Occasionally there's next to nothing to do in PS, so when I say "after editing" below that means normal light edits to a filter bonanza. It doesn't matter, I always finish in Lightroom.
On Import...
1. Apply lens profile correction on Import (and then undo the fisheye shots - too bad you can't exclude based on lens type like you can body). It's easier to undo it occasionally than do it to every image.
2. Perspective correction and cropping, together or separately. I try to frame things perfectly, but I don't. Automated perspective correction is wonderful and I've learned to shoot leaving room in the frame for these adjustments. You cannot underestimate how proper lines make a huge difference in a "finished" image.
3. Gradient tools to fix light changes. Skies get blown out, it's a fact of life. Directional light means that the left side of an image has too many highlights and the right side is too shadowed. I've used as many as 4 gradients in one image before any other edits just to get it balanced properly, but I'll be damned if it isn't easier to get it done in LR.
After Editing
4. Radial Filter to apply localized vignettes. You can do these in PS, and I wrote a blog on it before this was a thing, but this is a phenomenal tool to help make the subject of an image pop.
5. Noise Reduction at the end. If I have image noise I reduce it in Photoshop using Nik Dfine 2.0
before any light editing. But, at the end of an edit, judicious use of the Luminance NR slider can soften image tones and even give a painterly glow to an image depending on how far you go. It's one of those things no one really talks about, but if you dissect a lot of those LR Presets people sell you'd be surprised just how often they use that slider for effect.
Bonus Tweak
6. Use the targeted adjustment tool in the Hue/Saturation/Luminance section to do a color at a time. Don't know what I mean? Look at this picture of ducks on the edge of the water. Right next to the Luminance section you can see the circle with up and down arrows is highlighted after clicking on it.
Now, move your cursor over the water (which is sort of blown out) and click and drag the mouse up (to raise luminance) and down (to lower luminance) of only the colors associated with the point you click on (I'm clicking on the water below).
Repeat to alter saturation and hue of colors, realizing that this will alter those colors throughout the image and not just in a contiguous area attached to the click point.