Good question, I have only given it one credit but it is definitely easier. Made it to the 6th stage on my first try, usually I'm lucky to make it to stage 5 in arcade mode and I've been playing that on and off for years.
I think it is sublet, maybe some changes with scoring and coins, maybe a few of the bullet patterns are easier... When I find out for sure I'll try and let you know.
Not played it too much yet (one or two credits) and I'm far from an expert but the chain meter is definately more lenient which makes it a little more free flowing. There is also definately more coins.
Other than that I'm not yet sure. Not had much experience with this game and Mushi Futari BL has spoilt me with it's lovely slowdown.