I do uderstand where you are coming from .... Alas, I am not a suspension designer & unable to give you the guidance that you so obviously need
As previously mentioned .... This is a well proven & trusted suspension design.
On the subject of joint replacement, yes of course over time the joints will need to be replaced.
Joint replacement on all types of suspension systems need replacing from time to time .... After all .... They are a service part.
Spent the best part of the last 30 -40 years changing ball joints
In the case of the Mcphereson strut ..... I have changed a fair few top bushes/bearing assemblys.
It may intrest you to know that many of the early Triumphs used an almost identical front suspension set up as the Roadster, in it's day, thought to be well advanced engineering ..... My point is .... I had to change the upper joints almost as frequently as the lower ones, must have been some even loads in there somewhere
