I see what you mean. I think in your case I'd pick a paper that you feel is likely to be around for a long time and then get used to that so you can work in the same intuitive way as you're doing presently. When starting out with the new paper, do as you proposed yourself and find out which contrast grade you need to set on the new paper to get results as close as possible to your previous paper.
Also, IDK what the most recent EasyPrint really was; I don't think it was really an ADOX paper. I know that some 10 years ago there was an EasyPrint that was a pretty horrible paper with poor, mottled blacks. More recently I understand an EasyPrint has been sold that didn't suffer from this problem. It seems that EasyPrint has changed at least once.