DC-DC switching converter PCB design
As @Jasen said: this will probably work fine, and I also agree with the other comments, about keeping it small etc.

Some additional thoughts:


C6, C7, C8 are probably not necessary
Like @winny said: move L2 to the right. In order to do that, you could move C2 to the left, especially if you would decide to omit C6,7,8 (or at least 2 of the 3)
You can probably do with just one C3, C4 or C5
All the vias on the left, near the connector can go. Your connector is through hole, and that should be enough
All the vias near C4/C5 can go, except for maybe one or two
Most of the vias near C1 can go, max. 4 should be enough
The vias near C3 can go as well
If you would 'lower' the Vcc trace on the top, you could make room for the GND trace to connect the connector with C1, and not need any vias at all around your capacitors. You're only drawing 488mA, so that shouldn't be a problem
The vias underneath U1 are probably also for heat? If so, check that there is no solder mask on them
Besides U1, the other part that will become more warm/hot is D2 and maybe the inductor
I like the position of D2 and the current sense resistors :-)
What kind of inductor are you using? It's quite common to use something like this:

As long as it's a ferrite inductor, you're probably ok, just checking.


You might want to consider bringing the DIM pin out to the connector as well. Might be fun for future use... ;-) You can PWM the DIM pin, or apply 0.5 - 2.5V on it to make your LED dimmable.

You're really on the right track here, not bad at all! Just some thoughts and possbily some improvements. And of course this is IMHO.