My ideal syllabus would have 4 hours IF, the slow flight bit would see introduction of incipient spinning (note incipient , not full), a bit more nav, at least another hour of PFLs and the nav test would be separated from the skills test as a 2:30 long test is too much at that stage.
If done sensibly, it could be done in the 45 hours, or maybe even in 40.
And if those of you who have been private flying for over 20 years think these proposals sound familiar, you might be right!