I grow a lot of Cacti and Succulents and Orchids and I grow many of them side by side.
Grouping them by the amount of light needed and temperature requirement is my first consideration. Next I group them according to the amount of water they need/ observe dormancies, also ease of watering.
As an example Cattleyas and Pachypodiums/ Adeniums can perfectly happily grow in the same bright sun, except I will slow down on watering the Fat plants as they go dormant. But, here in NJ they certainly can take the same amount of sun and sit in close proximity.
My Stapelias are right now in the greenhouse, but I am not hitting them daily with a shower, as I slowly lower the amount of water they need. In a few weeks my Habenarias which will be dormant by then, will join them and I will only direct a slight spray over them, perhaps once a week.
Small Cacti can certainly sit on the top shelf under the glass ceiling next to small rupicolous Laelias and similar, just water the Orchids daily, only spray the Cacti once in a while. Dendrobium lindleyi hangs in full sun, Rhyncholaelias love the sun and warmth, etc the list is long...
Cymbidiums and Epiphyllum hybrids are a perfect combo, temperature wise and considering the same light conditions, also Dendrobium kingianum fits here and Schomburgkias, Laelia anceps and autumnalis.
I would think it depends on your climate and general set up, but in my experience I can certainly grow Orchids and C&S in close proximity. ( But not in the same container) I should mention that all my plants spend the Summer outside and the indoor season here in NJ in a bright and sunny greenhouse with a glass ceiling.
