I did almost the same trip on 23 December 2016 (excl. the LCY leg) to get home for XMAS. SYD - ICN KE; ICN - IST - ZRH on TK; it was fun. I almost fell asleep on the Xmas table on 24 December!SYD-ICN-IST-ZRH-LCY (Star Alliance J redemption) (OZ, TK, LX)
Was supposed to be a 34 hour trip turned into a 44 hour trip thanks to snow in London which meant my ZRH-LCY flight was cancelled and then numerous delays in London/Zurich. Finally got put onto a LHR flight but my bags came 2 days later.