I guess raised details is mostly something related to older kits, that's the way they did it back in the days. But, a good manufacturer, depending on what is needed for a particular subject, can probably can do both raised and recessed details nowadays. I guess good research of a particular subject by a manufacturer is essential to determine wether something needs to be recessed or raised. The trend is recessed though these day I think...even when in real life it would be slightly raised. Think rivets and things.
I guess it's a matter of taste wether you want to sand raised details off and rescribe them. Personally, I try to look up if details are depicted somewhat accurately (be they raised or recessed) and then determine what to. My suggestion would be try to look up some references and try to figure out whats there. Compare to your model kit to see what Tamiya makes of it and then determine what you might want or might not want to do about it.
Others may look at it as pure evil and will bring out the sanding gear and strip the entire kit of any raised details and re-do them recessed with scale drawings and the appropriate tools