Resubmitting to Yahoo repeated times is stupid, especially when you want to wait a few months anyway before you submit to this one. I'll tell you when you are ready to submit Yahoo. Some others you don't have to update at all, except for routine maintenance. Out of the major search engines, you will only have to work with a few. The really important ones like Yahoo and Excite will bring you most of your visitors.
People use search phrases to find sites.
It would be impossible to think of all the phrases people use to find your site. If you only concentrate on just a few then you are missing a lot of traffic. In most cases, if you search the search engine with just one search word, you will not appear in the first 200, let alone the first 30. Do not concentrate on trying to place well with one word. I use a log analyzer that goes through my log file and then gives me a report on the search word visitors typed in to find the Crown Jewels website.