ur 4x2x2.5 will be approx 550L true water vol discounting sandbed and LRs.
ur sump will be approx 150L true water volume if u r carrying on using the same 1.5x1.5x2 sump, which i doubt so.
total will be abt 700L, ur hailea is only able to cool 380L of water. IMHO, u had better go for a overrated chiller of abt capacity 1000L.
moreover, u set ur temp at 26 which is quite low. chiller hv to work longer and harder.
as for lights, as u intend to keep sps and clams, minimum, and i mean bare minimum. at least 2x250W MH.