I've done 3 kickstart shafts,1 bendix and intermediate gear in 238hrs on my 2015 ec300e. I've fixed the kick issue with a 2004 fsr 450 shaft,2nd hand ebay job.
The issue with the intermediate gear being stripped,could have been prevented, if I changed or lubed the hidden bearing behind it in the starter casing.There is also another bearing on top of the crownwheel where the the starter bolts in.I use a thin oil to lube this bearing too.
This bike had been an absolute bitch to kick of late, and equally hard to start off the button,It was showing symptoms of over advanced ignition,so off with with the stator rotor to discover a woodruff key that was only just in 1 piece,it actually snapped when I tried to remove it from the crank.It now starts as it should on both the kicker and leccy starter.
My advice is if your using aggressive trials style splat techniques on grippy surfaces,get some lapping paste and mate the crank to the stator rotor and check your woodruff key for wear.