As far as i know, oppening the stock hole, instaling in the glove box, under the dash and in a center console are the only ways i know of to add a new head unit for your sound system.
What i always thought was cool was doing it in a center console, floor mounted ones look best to me. the only problem with this i would think is looking down to change CD's,radio stations...ect. it could be sketchy while driving down the road.
But do what you think looks best and functions best for you.