As I like to move fast and invisibly and I stick mainly to Core Search & Destroy I'm keen on Ghost and Lightweight for perk one (so that takes up three tokens, as you need to use perk 1 greed, too), and I use Marathon for perk three.
To keep speed high I don't have a primary gun, and instead use the B23R pistol - with silencer attachment. The B23R burst fires three shots, and is arguably overpowered - perfect for running and gunning. Close up one press of the trigger will often kill, ordinarily 2 or 3 will do the job. It's three downsides are it's no good for long range, it has fairly low ammo capacity (but if you're keeping the silencer on and want the extended clip it'll cost two tokens to do so), and it's very hard to see the fantastic emblem I've put on there!
I need Engineer on, because without it I'm constantly being killed/incapacitated by betties, claymores, and shock charges. And because I have Marathon on that means using Perk 3 greed, too.
To round it off I usually go with a betty - and either a Black Hat or a concussion grenade, depending on the map etc.
Means I don't have a Perk 2, but there's nothing that appealing in there, for me. As regards only having one weapon, if you want a second one there's usually some lying around if you want one.
You get to permanently unlock one thing when you prestige.
First prestige I did Ghost. Second I unlocked the B23R. (And it doesn't lose it's attachments when you prestige - so the gun's available but so are the silencer and emblem etc.).
Means I'm actually capable of getting a few kills after prestige.
Need to permanently unlock Engineer, Betty, Perk 3 greed, & Black Hat on my next prestiges - though I'm undecided on which order they should be done in. Hopefully will get my third prestige this weekend. I'm currently Prestige 2, Level 39.
Have seen a few Prestige 10s lately, which is simultaneously impressive and sad. All look genuine (ie have put the time in, not cheated their prestiges somehow) - as they tend to have around 150-200 hours playing time on their combat records. I've got about 74 hours on mine, which is a lot for a game that's only been out a month. Would probably be a higher prestige if I played a different game mode, but I love search and destroy despite it's low "score per minute".
BTW, don't know if you're aware of it, but you can also prestige your gun, once it's maxed out. Means losing all attachments (though you get most back pretty quickly) but allows you to put your tag and your emblem on there.
