Hey Wanderingblade,i understand what you mean.
Speaking of the lyrics,they still are like they always were, but for me their music has somehow changed. There is now more of this hope you talked about, it is somehow closer to reality and the sound has more warmth,is more positive,more dynamic.
You are right with saying ...to the more crushing bleak atmosphere, since the albums before LFDGD were indeed more like that,more depressing imo.
I'm not saying that LFDGD is sooo much more different than the albums before but when i listen to it, i just feel a bit different speaking of the atmosphere and the feeling i get.
So i prefer TD and DO because they are a lot more depressive than the others imo.
I think the difference between the atmosphere of the last albums and LFDGD lies therein that LFDGD is just closer to reality as i said before, it's not just black, but white too,just like life is. Also due to the voice of Jonas,which has become more pressureful and higher in tone and gives this hope a whole different expression,makes it sound more real. If he sang those parts like"i keep on living in this my only wish"... he sang them different, almost every time in the same tone,like DO was, so there was just a glimpse of that "hope", it's like he always fell back again afterwards,into that black hole again, like"when did i say this,i will never leave..."
LFDGD is without doubt a good album,maybe just because it is a bit different,but i just can't get away from the others, just like them more
So please don't yell at me,it's just my opinion.