Eh, They admitted that the BGs and valor quests were pretty bullshit. The rest really wasn't bad. You can have a cloak now in like less than 2 months, including test of valor in its nerfed form.
Not sure why you need to do flex, you can get everything on lfr (obviously flex is probably simpler of course).
It's not like you don't get rewards along the way, I thought the questline, less the two REALLY stupid parts mentioned, was interesting enough. It's also vastly easier now of course, I remember spending like 3 or 4 months getting runestones before they changed it. But I mean, I've got cloaks on like 5 characters and it never felt particularly tough or time consuming on most of them. It'd be 'aww that was a bad week for drops' or 'oh wow I got 8 this week" and in the end they only finished it a week or two different depending on rng.