As a failsafe measure coupled with the fact you've never been to HHN Orlando before, I would probably recommend Express (plus it will likely be cheaper given it is a Wednesday).
Buuuut, I do also think it is entirely do-able in one night without Express, especially on an early Wednesday in the event, so long as you pay attention to early reviews and buzz regarding crowd interest and are prepared to be there rope-drop to park close.
If the goal is just to spend as little as possible but still bolster your chances, you may also want to consider the cheaper options too that aren't exactly Express but help you get a leg up on things such as the Scream Early ticket (assuming you don't have day passes already) or the after 10/11 (I think it is 11), half priced Express. I would caution against banking on the second option there though, as they do not always offer it (it depends on regular Express sales and numbers for the night).
I will also say that last year, oddly for us, Wednesday and Thursday were perhaps the two busier nights for our group, kind of bucking general trends from past years. Could have been the rising cost of FF passes that encompass all days, pent up desire to go from locals, increased interest in the RoF passes given how late they were announced, etc etc, but it is hard to say if that trend will continue!