Option A ) Stay at Everton, be the first name on the team sheet and fight for a Europa league play-off spot. Option B ) Stay at Chelsea, be a useful player from the bench, get paid more money and possibly win the CL, EPL, FA Cup and the League Cup. And "work with a manager who doesn't rate you", a manager's job is to get the best out of a player. I doubt Martinez could improve Lukaku to a level anywhere near that Mourinho could.