If I was teaching somebody I care about to fly, I would do the PPL stuff plus what is needed for IFR (IMC) flight and instrument approaches. That's the baseline for safe UK flying.
The IMCR is also pretty well essential for
pre-planned flight in the UK - even if many flights actually take place in what happens to be probably legal VFR conditions.
Sadly, a decent aircraft and decent currency ON TYPE are equally essential, and one can't teach those...
I am getting out of here before I get shot down by all those retired old boys, living close to the airfield, who say "you can go everywhere VFR, young man"
One more thing though... I found the IMCR training to be a real grind too, so these diaries make disturbing reading for me. The key to it being a lot more pleasant is to do it in a decent plane with decent avionics, plus building it up gradually and not doing the hard stuff until one has decent situational awareness. But that would take more than the min prescribed 15 hrs and I don't think many students would be too keen on that.