Ghost was well-known in its niche, but eventually, owners of these platforms have to make a choice: surrender your customers or get slapped with 'bogus' charges. Every communication platform that has 'ECC' in its name is a red flag for many, except if you are low-hanging fruit.
Threema, Wickr, and Wire are good commercial solutions if you can deploy them on-premises yourself. I've conducted assessments when some legitimate users were looking into these platforms. Even then, I wouldn't consider them more secure than the alternatives. Overcomplicating things is where the big money is in security, but I can guarantee that simplicity is undervalued.