Hi! I'm pretty new here, but based on answers to other similar questions, I think this is likely because the wait time is going to be high whenever you ride 7DMT, unless you can get there immediately after rope drop. If you really want to see the whole Welcome Show, you probably won't get there soon enough. Also you may also get much shorter waits at some of the other rides earlier in the day (Tea Party & Winnie the Pooh) which saves you a lot more time overall.
Here's a link to the predicted wait times for that day for the 7DMT: http://touringplans.com/magic-kingdom/wait-times/date/2015-06-07