The reason I specked out for a plastic diaper is because of friction rash or heat rash, plastic slides, cloth like does not, some of the worst rashes I have had where from fiction, in my manner of IC I need a diaper all the time, I will need to look at chamois cream as well, I have never heard of it and Vaseline does not work at all, in a lot of brands of diapers I find are not compatible to Vaseline of anything that has it in it, it attacks the glue that holds the elastics in place along the leg gathers and leak guards and have even had the inner lining separate from the leg gathers and have it all fall apart.
I hate tight clothing with a passion so a onesie would not be something for me, while they may work great the feeling of it would drive me nuts, Autism for the win, not