Wireless Router or seperate Access Point.

Hi,
I am in the process of planning a largely wired network but I would like to add wireless connectivity for my laptop. I am planning on having one 16port switch to which will be attached a router, all my wired devices and a wireless access point. I'm new to the whole networking thing but the way my logic is working at the moment is this will mean that as every device is connected to a seperate port on the switch, they will all be able to communicate as efficiently as possible. The only 'bottleneck' will be the connection to the router - but the internet connection is going to be a bottleneck anyway. The reason I want everything to run as efficiently as possible is because all computers (laptops and desktops) will be accessing all data from a NAS rather than their own internal storage.

The alternative to this, of course, would be to buy a router with a built in access point but I decided against this as, to me, that would mean all wireless AND internet traffic would be on the same cable (the one that joins the router to the switch). Also, if there is an advancement in wireless technology I will just be able to buy a new AP - whereas if I have a combined unit I will need to replace the whole lot - along with the fun or re configuring my router.

Does this theory of mine actually work in reality? - or is there a very good reason for having your router and wireless AP combined (aside from the financial advantage). I would appreciate any help you could give me - thanks in advance!