Voyager hate is hard for me to figure out. There are some really stupid ideas here and there, but if you just overlook the few bad episodes you can see a lot of good ones.
The same can't be said for Enterprise. Enterprise was terrible and deserved to fail. There is nothing good about it. All of Voyager's faults are worse in Enterprise, and it has none of the redeeming factors of at least seeing strange new worlds. I don't see how people can hate Janeway because she's bossy but accept the completely wooden characters of Enterprise. I'd rather there be no Trek than there be Enterprise again.
You know I feel the exactly opposite. I don't think VOY has as many strong episodes say TNG and DS9 but they weren't all bad. VOY was let down by it's premise and too little development in it's characters. Janeway, Seven and the Doctor made out like bandits. Chakotay and Kim however are both bland and boring. Their lines and contributions to the crew could be exposited by nameless cast members. Tuvok and Tom Paris had more charm to them, but both are under utilized. Tuvok being First Officer on VOY would've made a more interesting dynamic than Chakotay and Janeway. B'Elenna and Neelix were hit and miss but mostly miss. Neelix was supposed to be the breakout character of VOY but he was annoying and not very helpful. Torres had a crappy attitude and unfriendly disposition, which she scapegoated her mixed heritage as the cause of.
I don't dislike Janeway but I can the the writers/showrunners (Jeri Taylor, Michael Piller, Kenneth Biller and Brannon Braga) went the whole 9 yards in making Janeway a tough and commanding Captain, despite the bad decisions Janeway made throughout the series.
As for ENT, it had the misfortune of coming out at a time when the market was over saturated with Trek. Rick Berman warned Paramount about this but they didn't care. ENT also suffered from the first 2 seasons lacking direction. But when you look at the trend with other Star Trek shows
TNG season 1 and 2
DS9 season 1 and 2
VOY season 1 and 2
None of them make out very well in terms of quality and quantity of good episodes. The first two seasons are a mish mash of hit and miss. By season 3 for all the 80's, 90's and 00's shows though, is when the series begin the turn for what would define them. With season 4 being the reaffirmation of what was laid down in season 3.
TNG had Yesterday's Enterprise, Sins of the Father, The Enemy, The Defector, Most Toys, Best of Both Worlds 1-2, Data's Day, The Wounded, Redemption, Brothers, Family
DS9 has The Search 1-2, Die is Cast, Improbable Cause, Heart of Stone, Defiant, Way of the Warrior, Homefront + Paradise Lost, Sons of Mogh, For the Cause, Broken Link
VOY had Future's End, Fair Trade, Before and After, Scorpion 1-2, The Gift, Year of Hell 1-2, Mortal Coil, Message in a Bottle, The Killing Game 1-2, Hope and Fear
ENT had it's shot in the arm right on schedule with it's season long arc the Xindi in season 3 and season 4 moving toward forming the Federation we would see in TOS. But TPTB had run out of patience with Trek at that point and decided to drop the axe on the franchise. For the record both VOY and DS9 were threatened with cancellation during their 3rd seasons as well. Which is why they straightened up and relaunched the shows with Way of the Warrior and Scorpion respectively.
Had ENT gone on with Manny Coto as show runner, we would've gotten the Earth Romulan War in season 5. Season 6 and 7 presumably moving toward the founding of the Coalition of Planets. BUT never retreading the TCW nonsense that was injected in the first 2 seasons. Just like VOY dropped the Kazon and DS9 moving away from Bajoran internal politics of the week after their first 2 seasons.