Congratulations on getting the new car. There is no need for ECU cover as I have heard that it prevents heat form dissipating, though i have never heard about ECU gone bad with or without cover. No need to wash engine way. Once a month blow of dust and clean it with a damp rag soaked in mild shampoo or APC. Buy some brushes to reach to hard to reach areas, even bottle and feeder brushes are useful to clean the engine.
Use a good interior dressing on plastics and engine top cover to keep it black.
As for as tires are concerned it is personal choice. I am satisfied with Euro Stars and will again replace with Euro Stars after 60,000-70,000 kms.