The mistaken assumption here is that each quest scales the same way depending on the number of players. Quest 1 may scale in a symmetrical format keeping everything easy and predictable. Quest 2 may scale in a symmetrical way, but it is clearly a bit more difficult for a solo player to win than a four player group. Quest 3 may scale in an asymmetrical way, where the loss of the Hero is much more painful for the solo player but the Ally restriction is much more costly for the four player group. Considering the other LCG's, I'd actually be a little surprised if this wasn't done on purpose.
Some people just want a nice easy time fiddling with cards, just like some people play solitaire, something to do to pass the time. Other solo players will approach the game as if it were a solo run on a PvP MMO, purposefully throwing themselves into the deep end to prove that they can do it. While I'm not that last player, I wouldn't even bother having bought this game if I were the former. The rules given here are much closer to the former than they are the latter. Winning 25 out of 25 games is just boring to me. I'd rather lose 25 out of 25 but see continual progress toward beating the Quest. YMMV
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