The gouramis or apsitos could work - the main problem would be your water.
Of all the apistos, cacatuoides would cope best, though they might not breed. I have pH 7.4 but softish water (7 german degrees/125ppm with the API GH tester but 5 deg/90ppm on my water company's website). This is a common thing for south american fish, the ones that can live quite happily in hard alkaline water can't breed because the calcium that makes the water hard does things to the eggs. Although in a community tank the eggs, and fry if they last that long, would be eaten quite quickly. Fish that have been commercially bred will be more likely to do well in your water than wild caught ones. It is quite easy to tell the difference as with these cockatoo cichlids the wild ones don't have as much colour.
The only confliction might be if you did get cories and the apistos spawned. The female can get quite aggressive defending her eggs. But I have dwarf chain loaches, another bottom dweller, and my female apisto hasn't harmed them, she just chases them away.
Honey gouramis do prefer a slightly lower pH than yours but can cope with a hardness up to ~14 german deg/270ppm. These fish are all commercially bred, and it is very hard finding any wild coloured ones these days. I can only assume no-one breeds this colour as the female is silver-beige and people want colourful fish. Mine are the yellow form, and there is also red.