Well, I have read everything but the Jink series, except for comics not put into the Reader's Collections which I haven't been able to find. Like Fire-Eye, etc.
The stuff done completely by the Pinis is definitely the best. As for the writing-- I liked the New Wavedancers and Rebels series, which Richard Pini had a hand in the writing. The Shards series is actually pretty good. It wasn't drawn by Wendy but most of the story was hers. And it shows. The art in it isn't bad either. The Ember series wasn't written or drawn by either of them, and it shows. But the part of the Ember series with Lehrigen in it, even though the drawing wasn't what I would have liked, the story had the Pini touch to it. And that story does have a blurb giving Wendy credit for "helping the story find its heart."
Forevergreen-- I agree with Darkhan. It could have been good, but it wasn't. The plot had gaping holes, and the art-- well, they didn't even look like Elfquest elves. Sometimes you could only tell who a character was by their characteristic hairstyle or clothing. And as for muscle definition, it simply was non-existent. Once Door took his mask off, he looked like a 13-year-old girl! Certainly not the scary madman he was supposed to be-- it was very incongruous, feeling I was supposed to feel frightened of this pretty little elf. Similar complaint for most of the other male characters, too.
The BoTC series wasn't too bad-- writing or drawing. The Kahvi series-- well, it could have been better. Much better. What turned Kahvi from the shrewd, bold chieftess to an irresponsible, restless, selfish brat?
Rogue's Curse had too much action, not enough character development. It read like a superhero comic. But I liked it anyway. Especially the story written and drawn by Wendy in that book: it was intense, compelling, beautiful, profound-- everything I've come to expect from her.
So I guess if I'm frosted at anything, it's Forevergreen and Kahvi. It seems to me, given the themes of the series, that the Pinis would want to allow other artists/writers their freedom. They believe in that. But I think they gave them too much freedom.
There's my input.