These are great suggestions, but don't hold your breath waiting. There have been lots of requests for added Standard events, including added marriage-related items.
The problem with "custom" events is that they *never* link persons in relationships. So I can create a custom event of Marriage Intention (which might be recorded in a New England Town Clerk's record book), but the 2 parties would not be linked, and the Custom Event needs to be created for each person.
The Tree program has strengths and weaknesses. But it will never have in-depth capabilities of genealogical programs designed for the home computer. Some of the latter allow creating customized events as new standard for your own use (with their own GEDCOM tags). Some such programs designed in Europe might be even more flexible. This sort of feature will not be available in internet-hosted tree programs for the foreseeable future.
You might want to take a look at program evaluations by Tamura Jones on his blog:http://www.tamurajones.net/index.xhtml