That is something you need to decide we can’t do that , but usually in small spaces simple is best.

In a smaller space I would stick with one color for the cabinetry. White will help brighten up the space and feel more airy.

You’re not going to be able to do any of that. Mobile homes are not built to the same structural standards as site built homes. They aren’t as strong structurally, and can not support as much weight. You would need to completely structurally rebuild the whole mobile home to make changes like walls coming down, or installing heavy new cabinets happen. The money to make that happen isn’t worth spending on a depreciating asset that is not considered real property. It would cost way more than the value of the home to do any of that.