I don't like that column in the center, and I think if you removed that then the rest of the 'scape actually looks quite good I think!
Great post Albert! There is at least one advantage to having "more rock than you need" though...there is more capacity for denitration.
I have never been a fan of rock in the sump because of detritus build up even when using a filter sock. However, I think rock in the sump
can be beneficial for denitration
provided the sump area is siphoned of detritus at least once a month. Many people are not likely to do this maintenance though, so generally it is better idea to just not put rock in the sump.