Probably. (I should have mentioned, however, that we never do Volcano Bay, so you might need that extra day if you plan to go there.)
If you are okay with waiting in some longer lines, then you can probably forego Express Pass…just plan your days a bit more carefully. Express Pass, however, will give you the option to pretty much go entirely unplanned.
If you decide to get Express Pass, it will almost definitely be cheaper to upgrade to a Deluxe room. And, if you really want to be “pro” about it, and aren’t afraid to do a split stay, since you get Express Pass for the day of arrival and departure, you can book 2 nights at a Deluxe and get three days of Express Pass from it. So, maybe start at the value for 3 nights, and then Deluxe for the final 2. This gives you 3 days with Express Passes.
We stayed at Surfside Inn last August, so we didn’t get the Express Pass advantage, but it was okay due to extremely low crowds. We stayed offsite this past May, and still didn’t bother with Express Pass. BUT, crowds, while still relatively low, were definitely higher. DEFINITELY plan to rope drop and take advantage of the Early Entry. If you get through WWoHP early in the day, you’ll be glad for it because both Diagon Alley and Hogsmeade become almost unbearably crowded by noon. If you get them out of the way early, you can then focus on the rest of either park when everyone else is crammed into WWoHP!