The mousewheel is really all I use, though I do have xloc bound to q. I used to get accused of having weapon switches bound in UT2k3 all the time. You could bind something like pipedswitch or somesuch to automatically switch between any two weapons. Of course I never used it, but quickly switching weapons allowed you too "cheat" the rate of fire delay. Since my favorite combo was Lightning and Rockets, I just had those side by side in my weapon preferences and used mousewheel up and down. So you'd take a shot with the LG, and rather than wait for the recharge (slow!), you switch to the RL and let fly then switch back. Because Rockets are projectile weapons, you could frequently switch to the LG while the Rocket was still in the air and get a Lightning shot off as the Rocket arrives. I've been on the other side of these kinds of attacks many times and it's quite daunting when it seems like the person coming at you is using two weapons at once. I occasionally also use Flak and Shock this way, and essentially any hitscan and projectile weapon combo is good for it. A lofted Flak shell combined with a primary shot can also have this double attack kind of effect.
Personally, I think that adapting to using the keyboard shortcuts (1-0) for weapons would only improve my game in the long run, but unfortunately the mousewheel switch is so ingrained that I think it would take a long time to pick up the habit of choosing weapons a new way. Playing months and months of iBR in UT2k3 certainly helped me get used to switching weapons quickly and it's a bit easier because there were only two (Super Shock and Xloc) not to mention what it does for your aim. The only problem is, when you switch to NW, you'll probably have a penchant for the LG or Shock and you'll be very accurate with them so be prepared to be called a cheat.
Cliffs Notes
Acquire the habit of switching weapons fluidly in every available manner (mouse and keyboard) if you can. If not, it's just a matter of becoming comfortable with whatever method you choose through repetition. Do it enough and you'll master it to the point where people will think you have binds that switch the automatically. Start by always knowing what weapons you have. Also, adjust your weapon preferences in settings to suit your game.
Regards,
CChaos aka (currently) :NQ:Malice: