Just another newbie here, but I'd say no grommets on the needles, upgrade the size of your swivels, and drill the hole one size up from the barrel. I had to use grommets on 2 of my first ones, 'cause I screwed up on drilling the swivel hole
, I just drilled bigger and used the grommet, and yes I rolled the edges to the curve of the plug.
Like the shape on your poppers, keep a spinning!