Some aircraft in game are bitches to taxi, others are easy. Surprisingly, that is much like aircraft in real life.
For example, I've been in two De Havilland aircraft: a Chipmunk (which I've flown) and a Tiger Moth (had pleasure of sitting in, will fly sometime this year). The Chippy has true differential braking and a caster tail wheel. When the brake is correctly applied (4 notches), it is incredibly easy to taxi. The Tiger Moth on the other hand, has a spring loaded tailwheel (identical brake system on main wheels). The result? If you brake a little too hard, you ground loop. If you get off the brakes too quickly, tail springs back sudden and you ground loop the other way! The different tailwheel completely alters the taxing experience. And flying with a tail skid, well that's something different! Especially when taking off from a gravel airstrip! That can be a bitch and a half, but great fun
As for tricycle aircraft, well if you have a steerable nose wheel, reasonably easy but those with passive front steering can be a bit of fun. You guys should ask JackS about what used to happen to over-enthusiastic recruits in T-33s! If you were too rough with turning, the front wheel would jam!
To be honest, I think Il-2 is pretty good when it comes to taxing. The biggest battle is setting up your rudder pedals correctly and getting the sensitivity right (and for those using keyboards or twist sticks, you really can't comment on this as it will always be difficult to taxi no matter what you do!)