I think it looks great. You have a nice carpet for sure. I can see people are ribbing you pretty hard for the gourami in a small tank, but I have a different take especially since I keep a fish in a half gallon
If you can feed him as he would normally eat in a larger tank and keep the water changes in this one, pretty much any aquarium is insulting compared to not being in a free swimming lake or river and I see you said there is another tank you can move him to
Regarding the interplay of detritus as we had discussed, this tank will certainly accumulate waste if given enough time, months and years, it is new enough that the clean factor is holding strong in spite of low export.
It is true as you mentioned that changing only top water remove dissolved organic compounds in that water, but the solid waste produced and sitting in the system will gradually increase the doc making water changes needed more often, this will reveal in time as the tank ages and is a function of having accumulated detritus and decomposing compounds. Oil slicks w become more noticeable in time
Any tank that is a few mos old looks cleaner than it does at five yrs old for example, and thats the kind of time frame needed to see if a balance has been created where the keeper doesn't move any detritus around but the tank stays free of it through self balance.
The substrate, if tested, will indicate detrital organic loading through location specific bubbling just as mentioned if thats ever tested and photographed. Compared with a peroxide injected handful of new substrate not exposed to detritus holding it will bubble markedly, giving further indication of detritus not readily apparent to the naked eye
Any small tank with a catch and hold substrate design and some fish will indicate that as well. Some of the fish waste is landing and staying within that carpet as it degrades into smaller particles its just the tank isn't old enough to register an accumulation yet. Still looks nice and clean! We simply have a very new tank in the easy work phase and thats an enjoyable time for any tank. If the tank goes un exported for a couple years things w be different. Update in 2016 if you can
Looks great man I'm jealous of your nice even carpet.
B