Hi,
You can also add the pushpins when they are needed. For example depending on the user, depending on the size of the map.
If you really need so mutch at same time I have other suggestion. Copy the map to a TImage and draw the puslpins in Delphi. Maybe this go mutch faster. I think the copy of the map image will go very fast.
Or even better. Make a Transparant Form. Put the form in exact same size and position as your main form where mappoint is on, and keep it a s shuch. then draw icons on the transparant form. This way you have mappoint with layers and super speed drawing
Of corse yoiu have to keep this form on top of mappoint form, maybe tricky here and there ?.