Engraving on the sidewall is best left for a larger scale , perhaps 1/12th, or possibly 1/8th. Also, any 'engraving' to be visible would need to be hugely out of scale ( especially the depth ). Third each 'engraved' tire mold would then become a specific type and not useable for other representation....more $$$ to do another car with a different tire.
The interior on these cars were rather plain, especially by todays' standards.....perhaps the better thing would be an ' interior upgrade kit' ( borrowing this concept from the model aircraft hobby ) available separately so those who choose to entertain the expense and labor may do so.
Wheels can be the death knell of a model....too simple, and potential customers aren't happy.....too detailed and the price takes a quantum leap.....again, for those who want a higher degree of finesse, make the 'hi-def' wheels available separately. I have seen model wheels that include separate spokes, tension adjusters, air valve stems, etc......but at $40 EACH, in a slightly larger scale. Each manufacturer must make decisions on what can be included to manufacture a ready to sell model at the pre-chosen target price.
Someone, one day may remake this model at a higher level of detail....but at what price ?