I hope he's getting this type of advice:
you are a first choice at Everton and can develop and grow in a tough season - but not a relegation battle thank god!
Only Man City and Arsenal, maybe Spurs, are settled at the moment, with a vision and direction. The other 'top clubs' are in transition and you might play under the current manager, you might be out of favour within months. And Man City and Arsenal have first choice back lines. So why not stick it out, build your reputation and go after 2 years, you'll only be 23, and you can have a settled 7-8 years at a really big club. (even outside England)