54 or 52T spur and a pinion in the high teens or low 20's will be plenty fast, 3s will require different gearing then 4s for proper temps, there is no magic combo that will work with both. For the 2200kv motor I wouldn't run it on anything but 4s, the 2650kv motor would be suited better for 3s.
As for run time, there's a lot of variables involved but always going for the highest mah (capacity) packs you can afford/find is the way to go. I personally like to stick to 5000mah 40c minimum. Think of pack capacity as a fuel tank in a car, the more fuel you can put in the farther you will go.
| Cen Colossus GST-E |
| Stampede 4x4 | Stampede |
| Shelfers - Lunchbox & Blackfoot |
| Futaba 4PLS |