You can't have too many bass traps...[?]
Unequivocally: yes, you can. Too many of them and put the wrong the places they eat away of proper soundstage fill/size and kills overall energy and (natural) liveliness of the sound. It's about strategically placed bass traps, smaller ones at that and used sparingly - as I see it. To much bass trapping may have an alluring sense of bass control, but I'd rather live with the occasional unevenness of response to have a more natural overall presentation. I'd include diffusion predominantly over the Schroeder frequency and, again, light absorption below it to deal with bass modes.