Holy Water could be awesome on the point, where you have already aquired Blade of Darkness, but at that point, it would just weaken the Dark Forge. As the Dark Forge base dmg is about 80-110, the Angel here has only 20-40. Dark Forge has attack speed of 5s, and the Angel has 3s. As calculating, the level 1 Dark Forge does 16-22 DPS, and the Angel would do 6,667-13,334 DPS. And this is only level 1. Of course, the BIG bonus to the Angel would be that Luck increasing blessing. Until now, we haven't had any other type of luck than the Lucky Pants, but they are not consumeable (expect to Mr. Iron) and so forth, not much of a use at other towers that don't have any special abilities. For Beavers and Miss Jilly's they come in handy, as well as Holgar, but I usually use Holgar - Mr. Iron married, so I usually just feed all my Lucky Pants to the Mr. Iron.
And by the way Andy, have you checked on the potion idea I sent here?
Looks like a nice support tower and well designed. As its benefit deals with luck and item chance/quality, I really appreciate it. +1 for me.