From what I've heard, generally speaking if you have more than about 8 types, you should use a Type Catalog (what I presume you've been calling "type tables").
Type catalogs are comma-delimited text files that follow a specific format (see Revit Help or use someone else's as a guide). To work when loading the family into a project, the type catalog file must have the same file name as the family file, but have the .TXT extension.
We have our "master" type catalog files actually named .CSV, which allows us to double-click on them and load them into Excel. When done making changes in Excel, we save them back to CSV files then copy them to .TXT and then test them by loading the family into a Revit project.
There are several significant benefits to using type catalogs:
1) They provide users with a "data preview" before loading anything into their project
2) The type selection dialog seen when loading a family has a filter tool, so the users can reduce the list of choices very quickly
3) Users may load *only* the specific types they want into their project, instead of bogging down their project with loading all types possible
4) Changing type definitions (e.g. using Excel) is very fast and easy for you
The easiest way I know of to embed the types you've defined in your type catalog into the family file is to do as you describe: Load the family into a project (selecting all defined types in the resulting type catalog dialog that appears so all types get loaded into the project), place an instance of one of the types, then "Edit Family" on it and re-save it from the resulting Family Editor version to a new family file.
Just be sure all the types in the list turn black (showing they're selected) on the type catalog dialog that appears when loading the family before clicking OK.
A tip about type catalogs: The Model field in the family MUST have some existing text in it in the original family file in order to get the model text from the type catalog to load into that parameter. It's a small bug in Revit, at least as of the 2009 version.
Also, you don't have to put all parameters into your type catalog...only those that change between types. For example, if your family only comes in one voltage, you could put that voltage value in the family file and not add a column for it in the type catalog, and all types would automatically inherit the base voltage value.
Best of luck.
