I would suggest a full service before a remap.
Oil, oil filter, air filter, plugs. And any intake/valve cleaning that you can do beforehand.
On a previous car that i had remapped i did not feel much of a difference afterwards until i had a terraclean done. And then i realised the full potential. Albeit, that was aturbo diesel.
As the post above, remapping stresses all components, especially turbos. And turbos need good clean oil frequently changed.