I think anyone who is eligible, should take full advantage of the scheme.
You may need to make compromises on the car you actually 'lease' but, as you say, the cost difference compared to buying/leasing a new car without the Motability Scheme is huge!!!
Something like the MG ZS Electric car (Automatic) is free of the PIP advanced payment. Would I buy one? Hell no. Would I have one for a small monthly charge, knowing that anything and everything that could/would go wrong with it would be fixed and I would never be without a car? Of course.
Get yourself a Motability Scheme Pack, and read it carefully. You'll probably get the Charging Point installed FOC, if you have the driveway, and the installation is 'basic'. (By basic, I mean, they don't have to run cabling under 100m of landscaped garden for example).