There should be no GND under the noisy mosfet drains. They should have a rectangular copper plate via stitched to the surface layer to surface layer to add heat removal.
this rectangular copper area with vias... attached to what rail? the smt pad is the input... I can make a small copper area for each mosfet rail 5v and 3.3v.
Ok.
You are also feeding up to ~15 watts or more power through single vias at multiple places in your design.
you mean the output connector? what exactly.
See the attached image purple arrows.
You are driving 6v @ 3 amps through one of those vias, no to mention 4v @ 3 amps. If you think you can rely on a single tiny via to live through that, you will get some PCB mysteriously dying in the field after a week to a few months of use.
For the switcher, did you follow the datasheet recommended layout?
Also, the red one, hun? Power to the inductor, but also to the switcher from the inductor's Vin. I guess thatch ok as well.
Never flood fill when designing you PCB, especially power supplies where current handling matters in some areas.
The flood fill is the last step before the gerber output.
I need higher resolution prints without flood fill and proper net names on as many spots as possible.