Painting everything same color quite standard lah, if you are happy to have same color throughout. Developer give you freshly VP unit also usually everything same basic color throughout the whole unit. The color you pick is neutral enough to match most decor.

"Nicely painted" more important is painter put proper primer and paint the paint layers properly.

Bathroom if you want to paint inside needs a paint that can withstand humidity and moisture, if not you'll get mold spots.

Outdoors (outside/balcony area, potentially yard walls if yard isn't fully walled up) you likely not allowed to paint because it will affect facade (see your strata rules).