I'm not sure how much has changed. My DC are in P5 and P2 at the moment and while I agree the reports are a bit meaningless, I feel the attention they get and the breadth of the ciriculum is far superior to that which I received in my tiny Scottish village school in the late 1970s/early 1980s. I know my times tables extremely well but my main memories involve just working through the textbook.
Standard grades took a while to bed down. DB is two years older than me and he sat two SG and five O grades in 1986 whereas I sat 8 O grades in 1988. My year was on the standard grade ciriculum for a while for several subjects but there was a body swerve at some point and we ended up sitting only O grades. I think the history teaching I received in S1 and S2 was really poor, I remember colouring in pictures of Highlanders in S2 and my neighbour and I pissing ourselves laughing repeating "chewy bannocks". It didn't inspire me to study further.
Seven subjects is ok I think depending on the range the school offers. DB's were English, Music, Geography, Physics, Chemistry, Maths and German. I don't think that is too limiting. He has a Oxbridge science Phd and is a professor in a science subject at an RG university (MN's favourite...) but he would stil have been able to go in another direction with those subjects.
We changed timetable just after we sat exams but only from P4 onwards i.e. after O grades, otherwise we were wasting time kicking our heels around. Seemed sensible at the time.