I haven't heard of Ativan,
But I have been on both Risperdal and Remeron.

In my experience, I liked the Remeron for sleep. But that was it. I was put on it to help my anxiety from PTSD, but it didn't do anything for my symptoms except make me sleep better. And it didn't really even do that, it mostly just knocked me out and if I woke up again in the middle of the night, it made me fall right back to sleep in seconds. I also gained a lot of weight with that one.

I'm still on Risperdal and I like it a lot more than the other antipsychotic I have tried. It works well for my symptoms and I don't have as many side effects. However, it did increase my cholesterol at a high dose.

But meds effect everyone differently.
Those were just some of my experiences on those meds, though.

I hope they help you!