There is a lot of general information passed about cihlids which is just not true of all cichlids. To say African cichlids all have a particular trait is almost likely saying all American do this or that. There is a cichlid for almost any situation so if you want to branch out and get into somehting you have not tried, there is no reason to shy away just because of the common stories.
I would suggest going about the search in a more informed way rather than just writing off one of the larger groups of fish.
It will take some study to fit somebody in with your group but then it sounds like your group may not be totally fiting now.
With your High Ph, African cichlids might be a good place to start. No worry about finding ones who don't eat plants. It is a common mistake to assume they all eat plants. In the mbuna group there are all kinds of activities involving algae but that does not mean they eat algae. When they were first introduced, they thought that was true but then when they looked at what was really in their stomachs, they often found the fish were just "combing " the algae to get the micro organisms. But still the old stories are passed like gas!
Look at some of the open water bug eaters for some who don't eat plants.
And they don't all automatically have any special requirements as far as group size or M/F ratio. Find a site that tells you some of the traits of each group and you can begin to cut the list down as there are hundreds to choose from. The Labidochromis group has some small ones that might fit. Yellow labsare the most common for this group but Lab. Chisumulae might be a better fit for you.
Cichlid forum is a place that has a ton of info in the articles as well as a really large fish profile section.
This is a crowded 20 gallon with Chisumulae and hap ahli. The male is blue white striped but note the holding female above and behind him. They do not eat plants and they do not kill each other when breeding!