I think any disappointment would come mainly from a sense that we have marched up the hill, only to fall short towards the end. In terms of finishing in the top six or seven, that is. That feeling can be worse than spending the entire season in mediocrity, with no standout results. Winning away at Spurs and the RS sort of indicates we should secure European football to obtain maximum benefit from our efforts.
Undoubtedly Ancelotti has improved results if not performances, and has improved some players noticeably.
Say we finish 8th. It will be a marked improvement from last year but nobody in the football world will be pulling up trees, I wouldn't imagine Ancelotti would either.
If we finished higher, then despite all of the difficulties, it would say to me that Ancelotti found a way, as he does, to put some meat on the bones and record something tangible for the club at seasons-end.
It doesn't negate his work if we fall outside European qualification, but it infinitely increases the pressure for next season when things may settle down and we have more predictability.
Europe is probably seen as possible but not likely for this year, and I'll figure that was the view at the beginning of the season.
But, if not this year, then its a must next. Thats the way football works. There will be plenty of people waiting in the wings to dismiss Ancelotti as just another Everton manager who huffed and puffed to no avail otherwise, regardless of his spectacular achievements in the game. They were doing it when he was at Napoli and it would be the same here.