For short stays 4 days or less it seems to be a price increase. For 5 days or more it seems to be a decrease.
One way to explain it is that everything is a la carte now. You pick how many days, whether or not you want hopping, whether or not you want plus options (which now include disney quest), expire/no-expire.
We were going to get a 4 day park hopper. With the new MYW tickets a 4 day hopper would cost more and expires after 14 days unless you pay extra for no expiration. But since the price per day gets better the more days you buy, we are getting a 6 day MYW and the price is not much more than the new 4 day pass.
If you know you are going to make two trips of 4 or 5 days each, the most economical option is the 10 day MTW adding the no-expiration. That way you can use 5 days this time and 5 days next time, and the cost per day is the best.