For me, KP seems to be a very committed and hard working individual, and he has been a great servant over his time with the England team. He is one of the best batsman in the world on his day, and his record is up there with the best. To lose him at any point would be a big loss to the England team - he is that good - but to lose him right now would leave a big hole in the team. Seriously, since Collingwood "retired" (or was forced to, depends on what you think happened), they have yet to find his replacement. They tried Morgan, who in 16 tests averages just over 30; then Prior got moved up with Patel coming in at seven and that failed; then Bairstow came in and failed to seize his chance (though he does deserve another one at a later date); then they went to Bopara (again) and he failed (again); and now they're trying James Taylor, who showed some promise, but needs time to adapt to international cricket. But so far this year England have used 5 different number six batsmen, and so far none of them have been able to really take hold of that position. So can England afford to let KP retire, which then puts two spots up for debate?
I don't think they can afford to let that happen, because the hole that has been left by Collingwood is nothing compared to the hole that KP would leave. If they can't replace Collingwood, how are they going to replace a batsmen like KP? I'm not sure they can, but I suppose there are three ways they could do it;
1. Bell moves up to four, which then sees Taylor promoted to five, Prior to six, and Patel or another all rounder at seven.
2. Bell moves up to four, which then sees Taylor and another batsman at five and six, with Prior at seven.
3. Bell stays at five, which then sees Taylor and another batsman at four and six, with Prior at seven.
Now in each situation it would take time for that new team to gel, but the problem is the English public expecting things to happen straight away. Morgan's hit and miss start to his test career put a ton of pressure on him. Some argue it was his technique that led him to fail, but I think that the pressure and expectancy placed upon him played a bigger role. After all, Cook and KP's technique has never been perfect and has often been questioned, so it is not beyond possibility that Morgan could have adapted under different circumstances. But that pressure to replace Collingwood, and to win every match, has meant that every set up so far has been under pressure from the outset. I think England have found his replacement in Taylor, but if you take away KP then England have lost two experienced mid order batsmen who that averaged 40 and 50. With that loss, the pressure only gets more for Taylor, and for that matter, everyone in the team.
For me, what England need to do is keep KP at all costs, because at 32 the lad should play well into his mid thirties. Even though his form has been questioned at times, his lowest yearly average was 41.5 in 2010, and since then it has improved. So he is still contributing at a very high level and is very important to the team. As far as I'm concerned, having KP in that side is a fear factor for other teams because they know what he is capable of doing. On his day he is arguably one of the most destructive batsman on the planet and can turn a game on its head - like he did in the last test. Take that away and it will affect the England team. There might be questions around his attitude, and his relationship with management, but ultimately he is too good to let go and that is especially the case while a question mark remains around Strauss' position in the team. In the past three years he has not averaged beyond the low to mid 30s, and last year averaged in the late 20s. If anything, England need to prioritise keeping KP and potentially look at replacing Strauss in the side, with the captaincy going to Cook, and the opening slot going to someone like Denly who has performing quite well, or maybe Compton who has had a very good season and used to open for Middlesex. The worrying thing here is if KP does go, and then is followed by Strauss if he is dropped; that leaves three unproven spots in the team. So keeping KP until the sixth place is solved, and then potentially the new opening spot is solved, for me, should be a priority for the England management.
However, if KP wants to retire and no longer has the desire to play test cricket, or wants to pick and choose what tests he plays and which he does not, then I think it would be best to say goodbye now and move on, rather than wait around. As good as he is, no one is bigger than the team.