That is one big insult!
Well you didn't reveal the full story i.e. that the stuff you don't know about is mostly INOP anyway.
I submit that the money spent on gadgets might be better invested in training for the full Instrument Rating.
I would not agree.
Firstly the JAA IR is not doable under about £15k and that assumes you do it in Spain or Greece. Just the 50hrs at current FTO rates (sim, or SEP) comes to best part of 15k.
Secondly an IR is barely usable in some old heap. The Eurocontrol routings barely work below FL100 (depending on where in Europe you go; France is OK down to FL070) and you do need an autopilot to bring the cockpit workload to a level where the flight is enjoyable and to fly with the consistency and accuracy expected by ATC.
The FAA IR is a lot cheaper - especially if like most who have it you have built time and expertise on the back of IMCR flying, but (a) you still need the hardware and (b) EASA is threatening to require Euro papers on top anyway so this won't save any money. I think a lot of FAA IR holders will throw in the towel in 2014.
Most "gadgets" are essential for IFR, or VFR pushed to the limit on long trips:
IFR GPS (mandatory for IFR anyway)
Autopilot
Accurate fuel totaliser
Multicylinder engine monitor
Slaved HSI