I liked the sound of the ProAc DB2 and DB3s I've heard at a dealership. They do a very good job of faking their bass response-elevated upper bass to make the speaker sound fuller and rich in bass. If that is the case, I don't know what you can do to replicate this effect with speakers that are balanced differently. I have not worked much with equalization, but that might be the trick.
I can only suggest a lot of experimentation with the location of the speaker and location of your listening chair. Moving toward boundaries (walls) might help, as would any movement that takes the speaker out of a cancellation node.
It might well be the case of the wrong speaker for your particular setup, which means it is not a fault of the speaker, but just bad luck for you since you heard them work well in a different setting. I am not a fan of subwoofers, but that might be an option in your case, particularly ones that offer enough equalization choices. I doubt that any changes to electronics would effect enough of a change in basic tonal balance such that it makes sense going down that rabbit hole.
