Hi guys need some help for my new house renovation.

1) 2" height space enough for those small spot light LED? (http://www.dhgate.com/store/product/led-spotlight-led-ceiling-light-downlight/235209936.html)

2) I am doing L Box (without T5 longkang) but wonder if it is not bright enough to cover 13' x 15' (living hall) and 11' x 10' (dining area) and 9' x 16' (dry kitchen + study corner) square 4" LED

3) LED downlight ok in bathroom? and outdoor balcony ceilling?

Thank you