In terms of wages, its impossible to know till we see this seasons numbers if the 91mil includes CL pay increases which also go down without the CL. IE Modric gets 60k a week when not in the CL but 80k a week in years they play in the CL.
If they get a bonus for qualifying or a trigger for a huge salary increase and it doesn't go down when they don't qualify for the champs league that could certainly be problematic for Spurs.
However its also worth noting the 40mil they spent in player amortisation, when you look at the bulk of the spending, 25-30mil of that will disappear within a year anyway which would likely make it very close anyway.
Basically the numbers could mean a bunch of things, if the wages stay increased and they have another big spend, they'll take a huge hit. If wages drop to non CL levels in non CL years and the player amortisation drops to next to nothing then they could be looking at anything up to 20-30mil profits.
AS for if it ain't broke don't fix it, lol, 42 points in the first half of the season, 27 in the second half. If they maintain second half of the season form, which Redknapp showed zero ability to turn around, then you'd be looking Liverpool/Everton type 7th/8th position next year.
Spurs became entirely predictable and pretty easy to play in the second half of the season. They picked up 10 points at the end of the season against Bolton, Blackburn and Villa(win win draw), then won against Fulham in the final game of the season when Fulham had nothing at all to play for, it rather flattered their second half of the season and boosted their second half of the season points tally by over 50% in just 4 games, against 3 of the worst in the league and just about the worst away form team ever.
Basically, if things went on the way they were before he was fired, Spurs were facing down a truly awful season next year.