Ok, I've tweak around xperl's party option. As you can see, I've uncheck everything but you can still see the party's hp and mana.
I guess I'm stuck with having to deal with party members in my screen.
Oh, I've also checked x perl's cast bar. I have to say, blizzard's castbar is much better. Since xperl's background is dark, you may not notice the enemy's cast bar. But blizzard's one is clear and easy to spot.
Which mean xperl isn't much of a use to me. Although the 3d portrait does look nice...