Attract, impress and welcome! There is no need to change the expression of the building and architecture. Follow the same theme as the shopping centre. If the light clashes with the architecture it can seem distorting.
Make sure that the entrance is clearly marked. This could be done with light as an effect, for example with a luminous surface luminaire. It can also just be enhanced with light, like a well-illuminated sign or coloured light.
Directly aimed light has a dramatic characteristic and will create an impression of contrast. Soft light from big surfaces creates a smooth illumination with gradient shadows.