Renovation of a 1960s house: Questionable expert recommendations?

The expert is either good (because he does only the absolute minimum) or has not yet progressed beyond the year 1990.

If there are at least some financial resources, I would do a proper renovation and then also take advantage of substantial funding. Then you have a house that is prepared for the future.
Who wants to have such an energetically catastrophic house in 15 years (as of 2035). CO2 tax without end.

The expert is good.
This is an age-appropriate, sensible renovation.
A heat pump only makes sense if you really insulate comprehensively and also switch to underfloor heating.
I wouldn't do that; it's not good for old houses.
However, you are right about insulating the top floor ceiling/roof as well as the water pipes.
You can leave the heating pipes inside. It's a closed loop, so there is hardly any buildup/corrosion.
I don't think CO² will become so expensive so quickly that the additional costs would pay off in your lifetime.

I don't think CO² will become so expensive so quickly,

Ask our next chancellor. I'm glad I switched to a heat pump and photovoltaics.

Ask our next chancellor. I'm glad to have switched to a heat pump and photovoltaic system.

If that actually happens, I'll be happy.
But that doesn't change anything about the CO² prices.
The economy will continue to set the direction, and it will make economic sense to burn gas for many years (decades) to come.
Nothing against heat pumps and photovoltaics, but there is no reason to panic.

... I am glad to have switched to a heat pump and photovoltaic.

I cannot judge the facts here, but there are also opinions that a heat pump is not worthwhile due to significantly higher maintenance costs compared to, for example, a gas heating system - despite the CO2 tax.

How about a wood pellet heating system? In a house we visited, that was the energy consultant's recommendation plus facade insulation (presumably due to thermal bridges, I assume..... Actually, so far everyone has told us without exception that for these old houses, you should generally avoid insulating the facade afterwards).