Choose sharp colors. If you do not feel like using soft light hues, then feel free to go for sharp colors instead. For this to work, your furniture pieces will have to have sharp and bright colors or prints as well that contrast well with your walls.
For those renting out a property unfurnished, bright / sharp colours may put the prospective renter off if they don't have furniture that would fit in with the decor. But, I would agree that if the property was to be furnished, this style would appeal to modern or young professional type of tenant.
Generally though, so mainly aimed at unfurnished properties, I think the standard creams and magnolias are too boring these days and for my BTL properties, I mainly target the 25-40 year old bracket and decorate as follows:
Kitchen / bathroom(s): Pale blue / Pale green / Pale grey
Lounge: White / Pale grey
Hallways / Stairways: White
On each occasion this style has always received very positive feedback with a bright clean white on entry and fresh modern appearance in the other rooms. Obviously the kitchen worktop and cupboards appearance and style will have a bearing on what colour fits but that is why I have a versatile range that fits with a variety of units.
Plus, with only using the 4 above colours throughout the whole property, these are regularly on some form of offer so easily sourced at reduced prices.