Just looking at the same thing yesterday and all the old posts here on AMM about spots. Think about getting LED ones and not halogen as they are not as energy efficient at all. HAlogens are a bit like having an F rated fridge and LEDs are more like an A rated one!! Slightly dearer in the beginning but pay for themselves over time, also LEDs last 50,000 hours and the others are rated for 2000 hours.
Worth looking into to I reckon, we are doing a 25ft x 14ft kitchen dining room extension so not too disimiliar to yours.MAybe ask your electrician what he thinks about it.
Muffin