I think you feel guilty because it sounds like you're basically still in a relationship. Honestly you should talk to your ex about this and see how he feels since you've basically asked him to wait for you.

We really hope to get back together in the future and are kind of planning on it once I am ready. However, we didn’t cut communication and fully still act like a couple. I would like to experiment more with other people

It kind of sounds like you're leading him on, or gonna really hurt him. You gotta talk to him about your plans.

. I also know that he is still all for me and he is not interested in seeing anyone else and wants to wait for me

I would say before doing anything you gotta talk to him about this openly and honestly since it's very likely hes still under the impression that you dont wanna see anyone else either. Tell him you want to see other people. It isn't fair to make him wait while you experiment and you're gonna really hurt him. If you guys are both okay with seeing other people do it, just know it lowers the chances of getting back together. Just know that if he doesn't like the idea of you seeing other people you have a choice to make either fully break up with him or keep waiting for whatever you're waiting for.