He can bat at No.5 or 6 until we find better batsman to replace him. At the moment we have found 1 batsman who can snatch No.4 spot from him (again at team's interest). That is the need of the hour, let's call for that. Let's be practical... Who knows he can start batting well when pressure is released...
Similarly he should bat lower down in ODIs too (No.4 or 5) In T20s he should not do this non-sense of opening (in fact its one format he can even retire from - at least in International T20s, he can do whatever he want in IPL - its left to him & his franchisee! In fact if he was playing for a proper "want to win" type of IPL franchisee - like MI/CSK, he would have learnt some good lessons about his role in a cricket team from time to time. That's why he sticking to RCB who lis just like spineless BCCI... Still RCB though is a rubbish/dumb franchisee on its own did had the guts to throw him from captaincy for the first time, if I remember correctly!)
Lets think levelheadedly! Let's not go the extremes on either sides! Sometimes experience is needed, but it should be utilized in a better way...
I think a similar thing happened to even Sachin Tendulkar at one point of time in his career and many wanted him to retire... But thankfully we found Dhoni & his young brigade (Yuvaraj, Raina, etc) who took the responsibility and released the pressure so that he could put his career back on track... Also in tests Sachin had Dravid, Ganguly, Sehwag, Laxman who all came bit later (juniors to him) and shared the responsibilities & roles! But unfortunately Rahane, Pujara, Rohit are all seniors to Kohli... (only Rahul is junior - but he is low caliber player) And Sachin was a much superior test batsman than Kohli so he could bat at No.4 till his retirement. Kohli could have been a superior ODI batsman had he concentrated properly on his game! And like Sachin, Kohli should also have retired from T20s at some point (as T20 is for energetic youngsters). Sachin was at least not this stubborn and arrogant, so other players flourished under him.
Maybe you are right, instead of wasting time to teach Kohli & asking him to to be polite it is good to get rid of him altogether before others also start learning his arrogance & dominance!