I just don't play hidden at all. DT when I want to rank up. Most of the songs that actually give me PP are DT'd without hidden. I have no idea why HD would make a song easier, you're losing approach circles which help with accuracy.
HR will almost always be easier than HDHR
just as DT will almost always be easier than HDDT.
HR will almost always be easier than HDHR
just as DT will almost always be easier than HDDT.