Is there a limit

All of those dress codes sound confusing. In order to truly have a black tie event, you need to provide the service level that is described by the words "black tie". That includes valet parking, plated white glove dinner, top shelf bar, live bands, formal venue, and more. If your plans don't match the description, I would avoid using the term black tie. It's really specific when you're talking about etiquette. In most cases, it's not appropriate in the etiquette sense to specify a dress code on the invitation, the exception being a true black tie event.

The formality of the venue will usually dictate to guests what the expected dress will be. If it's an afternoon reception in a park, then no-one will think to wear a ball gown. If it's an evening event at the Grand Hyatt ballroom, then a more formal outfit would make sense. Usually the style of the invitation will help guide the formality of the event, embossed being more formal.

If you're going to put anything about attire, I would stick to just having it on the website, vs the invitation.

A black tie event is actually not a dress code, it is the level of formality of your event. If you are hosting a black tie event (ie, extremely formal venue, live band, fancy plated dinner, over the top decor, top shelf open bar, entertainment, valet parking, event begins after 6:00 pm, etc.) then stating it is a black tie event (or black tie optional) on your invitation is perfectly acceptable. People will understand the dress code expected of them if you are hosting a black tie event. However, if you are NOT hosting this level of event, then requesting black tie or black tie optional would not be appropriate. In that case, you would let the formality of your venue be the guide (ie, cocktail, semi-formal, etc.). You would not include that information on your invitations though; you would put it on your wedding website.

It is best not to be too specific he way the guests are dressed. It should not be a concern of the bridal party standing out. They will be distinct because they were seen alongside you at the ceremony. Plus, you really do not want to compel people to buy something new for your wedding. But, on the other hand, it does help for some guests who are less aware of dress levels to share some inspiration photos of what you see as style for the wedding.

If you feel like making a few requests to some friends/guests to add some color, you could just tell them directly. But keep it only as a preference. Anyhow, it is not how people dress that matters -- not even for the pictures. The main thing is the celebration of your marriage.

It is actually considered improper to dictate a dress code other than to indicate that the wedding will be black tie or if there are venue requirements. As mentioned, "black tie" is not a dress code, it's an indication of a formal event, to which guests would dress in formal attire. Guests are considered adults who know how to dress for a wedding at a given time of day or year. Likewise, designations such as "creative black tie" have no meaning or place on a wedding invitation and are only an excess burden on people. Many men own nothing in that category and it's not considered traditionally appropriate attire in any case.

The default for a wedding that is not black tie is semi-formal attire but you don't need to spell it out and shouldn't. The terms "formal" and semi-formal have so many meanings to so many people these days that they have lost all meaning, even on other types of invitations.

Also, to add to the above, wanting your guests to dress according to a color or a theme is not appropriate for any reason, including to make your bridal party stand out. They are loved ones, not props.