When Allardyce took over, we were in 13th place with a -11 GD and 9 points behind Spurs. We are now in 8th place with a -12 GD and 23 points behind Spurs. This clearly shows that 1). We have not improved and have in fact continued to fall behind 2). Our GD has not improved and has slightly worsened 3). We are only 8th because the league has been very poor this season from the top 5 down and 4). Allardyce is clearly not the man to take us forward. He has done as well as he has ever done since managing teams in the premier league. This was a season that if we had performed, we could have finished quite high.
Allardyce wont get sacked, he has done what he was brought into to do i.e ensure that a crap team never got relegated. If he goes, it will be by mutual agreement with a thanks and good luck.
There is a problem with your argument because quite simply, it's completely biased as usual against Allardyce.
Spurs are better than us in pretty much every department and finished 2nd last season - 25 points ahead of an Everton side that had a 25 goal a season striker in it. We were 9 points behind Spurs at the time you mention because we were only 14 games in to the season. They have also improved a lot since then which is why if they win their game in hand they will go in to 3rd position. The goal difference argument is another selective argument that is far less important than actual points.
You say we haven't improved. When Allardyce came in, we had the 3rd worst defence in the league (28 conceded) - with only West Ham (30) and Stoke (29) having conceded more than us. Since he has been here we have the 9th best defence in the league (so have gone from 18th to 9th). From 28 goals conceded in 14 games, to 26 goals conceded in 22 games. That looks to me like an improvement.
In the time that he has been here, we have gone from having the 13th best form in the league, to the 6th best form in the league. The results have improved, the performances under him haven't really and that is where he should be criticised.
I agree that Allardyce is not the man to take us forward.