I contacted my insurance company before accepting my policy to clarify what they meant by modification. I was told that anything fitted at the factory was not classed as a modification so they didn't need to know.
I know in the event of a write off after the first year they'll screw me for the lowest possible amount they can give me which is why I took out GAP with the full replacement cover so I have that little bit more reassurance. I just look at it as another option to add onto the list
Options are mostly worthless when it comes to trade in time but that's all part of the depreciation. I intend to enjoy my car with all the options rather than worry about how little I'll get back for it when I come to trade it in. Live for today and enjoy the car while you have it, depreciation isn't worth worrying about