I'm back from time at the beach! And while I'm no 30-gAy, I've got some thoughts on your decor.
You've got wonderful ideas about the bunk room, but maybe focus on the living area given budget constraints. The bunk room is great for what it is right now. If you want a change, try solid color quilts in a dark khaki which go with the carpet color to add depth to the room.
A couple ideas for the living area:
A change of thought! Think about keeping the sofas as they are and spending your current budget on changing the wall color, adding curtain panels the color of the walls, iron curtain rods and a couple comfy chairs in a neutral color.
Bring the chairs into a conversation area with the sofas. Choose a color now for the sofa slipcovers to coordinate with the chairs and do them as budget permits. Tone down the current sofa colors with a couple neutral pillows that blend with wall/curtain colors.
Your room would benefit from added depth and warmth. Wall color is the best way to add that. Do paint a warm neutral! Think about bringing small touches of the black from the kitchen into the living area (maybe dining chair upholstry?) and adding an oversized wood (white?) coffee table to put feet up on.
You have wonderful room sizes, a great kitchen and hardwood floors. Study Coastal Living Magazines and add some coastal touches. Replace the faux florals with hurricanes filled with shells found on the beach and so on.
Just my thoughts! Hope I helped a little. You've got a great place!
jo