Interesting you mention, all text fields as RTF fields. In that case why still use multiple fields is the first thing I wonder?
It sounds to me like your requirements might be coming close to, a Schema with a single RTF field, so the editors can work like they do in, let's say Wordpress ;o).
I always try to justify the usage of RTF fields in my Schema with the actual use case. Does the field require user formatting or the ability to place images or links in the text? Can I not get away with external link, Component link or multimedia link fields? Then I'guess it will have to be an RTF field. It all comes down to structuring your data, but you have to keep it easy to use for the Editors too. Too many fields in a Schema is not good, just having a single one is usually also not a good choice. But in any case, make sure that each field has the right format, that is a simple choice for date and number fields, but when it comes to text, you have several options to choose from.
To make sure these RTF fields are used correctly, you can consider setting up its restrictions, so remove all available options you don't want to be used in there and possibly also invest time in using the XSLT on the RTF to clean it up before every save.