Good advice right there ---- I agree with everything you say.
Yes, the ECU is expensive, but it is VERY easy to replace it ---- right under the driver's floor panel and, as you say, totally plug-and-play swap.
Cost of new Skyhook shocks keep going up (if you can even find one anymore) ---- last time I checked they were about $1400US each !!!
The sensors are fairly cheap and easy to replace, but everything else in the system is very $$$. There's a reason why a lot of folks just switch over to after-market coil over set-ups (non-electronic). If I had one or more failed Skyhook shocks on my car, I wouldn't bother with replacing them with OE units either.
I'm okay with putting in a new ECU ---- so long as that is the only problem (failure) I have. My only real issue with that is, AFAIK, Maserati never revised / updated the original ECU unit ---- which, obviously, has a serious design flaw. So, if you do decide to replace it, you're still stuck with the very real possibility that the new one will crap out too