I would do an access cab, run out of room right quick in the regular cab. I have owned both, that extra storage space is awfully nice right behind the seats. I'll never go back to regular cab pickup, well maybe the latest Tundra, it has about the same room behind the seat as an Access Cab Tacoma.
I used to sleep in a regular fiberglass topper, that gets old real quick, jostling gear and what not, even with a sleeping platform...lack of headroom makes it like sleeping in a coffin.
As the others have stated...I would look for a Wildernest, Flippac or a topper with a roof top tent. Quite nice to change clothes in a shelter standing up, than on your back on top of sleeping platform.
As Chip was saying, I would stay away from a full on conventional camper...weight adds up quick! Go light go fast!
I use Search Tempest or Jaxed Mashed to do mass craigslist searches...
http://www.searchtempest.com/
http://www.jaxed.com/cgi-bin/mash.cgi
Nice video of a RTT.
http://www.youtube.com/watch?v=75SgD8jG2us
AT Flip Pac
http://www.youtube.com/watch?v=nTZ2-o5kmKE
As for suspension, I like to tinker and adjust it to fit my (ever changing!) needs. Good set of coilovers such as Fox, Camburg, Icon....and custom Deavers or Alcans in the rear with emulsion shocks from said manufactures. While it might be overkill, it is a step up over Old Man Emu. Lets say in the future you want a bullbar and winch, all you have to is swap out coils and adjust the valving. Plus they are rebuildable...money is saved in the long run...where something like OME you have to replace the entire thing if it fails. And given enough time...everything will fail.
In the end it all comes down to how much money you want to spend.