I had posted this question / suggestion on Inventor forum but then thought to post it here too. See below link.
https://forums.autodesk.com/t5/inventor-forum/inventor-to-plant-3d-through-pcf-isogen-files-post-1-s...
Inventor has very limited list of Skeys to choose from. It would be good have an option of custom skeys.
We do modelling in inventor and generate isometrics in plant 3D through pcf files. So its very important that the skeys are same in both softwares. Plant 3D has option to have custom skey, which is very useful when we have custom / non-standard parts. It will be good to have same functionality in inventor as well.