Salary sacrifice is basically paying for a car up front before tax & NI – so it lowers your overall taxable income. You are still liable for BiK, but a BEV will be cheap as you have stated above. This cost is offset to all or some degree by the reduced tax & NI payments you will make on your salary – clearly a high rate taxpayer will save more from the scheme at 40% (or 45% for those really high rollers).
The only other up front issue is if the scheme includes all the on-road costs or not, many do, but again, if not, with a BEV these are not exactly high, servicing etc is cheaper and there is no road tax.
Mortgages and loans would also be based on a lower salary as the sacrifice scheme is included – but then, any car loans you take up would also reduce your overall lending capacity, so no big change there either, unless you had a fully paid up car prior to the scheme.
The final thing to check is how the scheme may affect your company pension and /or sick pay, that kind of depends on your workplace.
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