How do you use your dildo during partnered sex?

I bought my SO a dildo last year. We've ended up using it more than I thought we would. I love using it on her while she's touching herself because I get a better view of both activities. Sometimes after I've cum and she's cumming again she requests it because I'm too sensitive but she likes feeling filled up.

What I'd really like is to have her ride it while she touches herself, or while I'm touching her. It has a suction cup, but it's tricky. I brought a little bench into the room and she stuck it to that and rode it, but could not find a good position. When she was directly above it, it required her to squat up and down which tired her legs in no time. I told her to put it a little more behind her, and lean forward with her hands on the bench and grind on it. She did that, but with her hands on the bench, she couldn't really touch herself and the angle was prohibitive for me to touch her.

Any ideas or tips of other places to stick it, other ways to use it, angles, surfaces, whatever. I'm looking for ideas.

Thanks in advance!!