I realized, after I read the extensive notes on the wizard, that the hopelessly broken wizard is only hopelessly broken if you have a player with any skill whatsoever. Any skill. In fact, using sleep as a room nuke, the elf's ability to walk around in light and darkness, and using any of the many empty boxes in the store room for a long rest, the wizard, alone, could VERY EASILY solo the entire adventure.
Have you ever backed up in Diablo when there were too many critters? There you go.
So, other problems:
My fighter's only "problem," was that he was kind of boring. I Hit. I Hit. I Hit. I Hit. I fell asleep just now thinking about it.
The clerics had a combination of silly at-wills, a defender thing that made no logical sense at all (you can defend [give advantage to] two people, for example, from different attacks, because you have a shield, even though those people are each <5ft from you, even though they may be >10feet apart (because YOU, the cleric, actually have width, in reality, you're not a point. So if you're taking up 1/2 of a 10ft square, that's 3/2 squares from side to side you are "defending" with your shield, magically, without magic.
You know, the DM thinks, I don't know, you turn your shield to defend the guy on your right flank, you are not defending the guy in front of you, right?
Apparently, this is the "old school" way of thinking, which apparently involves hard math. The idea that defending someone to your right that you need to MOVE to defend leaves the guy ON YOUR LEFT undefended. People have written entire novels on their problems with the clerics, so I will let it go at that.
I seriously, seriously, think the only purpose in "advantage" in rolling two dice is A. To sell more dice. And B. To sell every DM who has to do disadvantage on more than one or two monsters at a time a die roller. Maybe it's a die-roller ap. Whatever.
The rogue's comments were largely about feeling a lack of special abilities, which could be fixed with "thieving skills and non-weapon proficiencies." His words, NOT MINE. Technically, there is nothing saying a fighter can't sneak just as effectively in the right scenario.
OVERALL, the problems with the characters are summed up thusly:
My group plays as a group. When they are coming up with characters for a campaign, they talk to each other. They plan to use their unique abilities based on what they want to play, what they want to do in the group. Having a system where all players can each do all things defeats the 'serving a unique role' purpose. Since a long rest restores all hp, even the cleric's healing ability is replicated BY HIDING IN A BOX.
The next installment is about logic, worldbuilding, and the broader problems, and will not be interesting to non-DMs, I think.