1) It's cobblers to say that this is normal, worth checking tyres (different types?) & pressures and alignment and 2)
2) This sounds like maybe ball-joint wear which is a common problem and might also be responsible for 1). What mileage has it done, I notice you say it's done it from day 1 but was it new or used?
3) Not starting first time occasionally (ie once in 6 months) is not unusual on the IS2. Could be the transponder in the fob was dodgy when it was a regular problem.
I have to say I don't think Lexus dealers are neccessarily better than anywhere else - it's about the individuals, not the sign over the door IMO.