How to stay well grounded?
I'm not quite sure where you are coming from so I've tried to answer how I'd do it.

If you need to have several individual components connected to the ground plane (blue) then use individual vias to connect those components to that ground plane. That is usually better practice than having a top localized ground plane.

If you need a top localized ground plane (such as for some SMD chips) then stitch that down to the underside ground plane with several vias.

A top localized plane stitched down to the bottom plane may look like a loop in some respects but it can be argued that it is two ground planes in parallel in that local area.

Vias can be an issue of course - they have inductance and that inductance can make a localized top plane "less strong" than the underside ground plane - this is why several vias (all in parallel) will reduce that inductance.