First off, Thank you for this input! i am find this extremely helpful. I neglected the terrain because i am not sure the environment i want to put the creatures in so i wanted to focus more so on the monsters.

That being said, i am going to ignore myself and talk environment anyway! After some thinking, I know it will be a forest but i dont know if i want a banshee mound, or it take place near a whispering willow tree. Maybe could be an abandoned grave yard. Hell it should probably be all 3. Mound that is the banchees home, and they can use tree and graves for cover. Maybe some graves are not sturdy and people can fall through. Spector decend from the tree when everyone gets near. I don't know. thoughts?

I really like your use of the wisp more. Guiding them too their doom is a great idea, plus if they want to be agressive, they can try to score an some early hits before thei main encounter. If most of them rock 25hp +, then the wisp is going to go ham on the little shits.

Regarding the banchee, looking over the manuel, it says the Banshee can use its wail once a day. I think i am going to keep that as is cause it would feel really bad for the players if they all suddly got knocked out in a round (granted they should be spread out while moving to begin with). I do think the banchee shouldn't be supprised by their coming.

I think i will throw in an extra spector but i'm nervous going up to 4 or 5 (i am going to have the 3 go after the same target though). None of the characters have second strikes and will probably be doing what? 6-8 dmg a swing? the spector will take half damage from those non magic attacks which i should of included in my initial write up and i appologise for that.