Well judging a thing for their cons isn't a good thing. Whatever the game was, u have to accept its current state and u have to accept that it isn't back stepping ever.
that said, LFR has these good sides -
1) No fixed schedule: this single handedly, what made LFR popular. You might be a busy mom, a guy working 2 shifts, a normal raider doing 3 nights a week, whatever u r or whatever ur schedule is got an hour free? u can q up and get into LFR. Then u can see content and get a bit of gear. And no the gear isn't free. Chances r most ppl don't see more than a piece of gear per week. So, QQing over lfr giving free loots is very pointless.
2) LFR allows ppl to escape premade groups: lets face it, not all ppl has same mentality, if they had there won't be a forum and any discussion. A person can be invited to a very nice group which is very nice experience or she can be invited into a group of jerks, who rants on even silly mistakes, which is very bad experience. And experiance as such in past, makes ppl shy away from grouping, unless they know the group to be nice. LFR now gives these ppl a nice way to avoid these. ppl now in LFR simply ignores jerks or kicks them, and simply forget that incident. in their mind its just an hour long event they can completely forget about.
3) Gears: Gear is something craved by all. an upgrade is a upgrade. It helps casual ppl to have a sense in character progression. to see them getting stronger a bit with every upgrade. For alts targeting normal mode raiding its a great opportunity to have a few piece of gear that takes them to the minimum ilvl required to enter normal mode. This aspect is very much helpful raiders who r targeting for normal/heroic progression. once u r downing bosses in normal, u r good to go and ur participation in LFR will be less and less every week. Older tiers raids r pointless now. as LFR gear out levels them greatly, also using lfr, u dont need guild mates to carry u through normal mode for gears, which saves time.
here is some supposedly bad side -
1) ppl get bored fast: well ppl who get bored fast will get bored anyway. its our nature. on how much we can concentrate on something. This can't be helped. U can say increase difficulty, but doing so would make ppl bored faster and frustrated. A challenge which u take on willingly is enjoyable, but forced on u is not so much. and Wow being a game, forcing challenge on ppl, will make many of them quit entirely. U may think "Good riddance!", but think again, more ppl remaining in game means more money to bliz and more content for every one. clearly this is a win for all side.
2) ppl in lfr is bad: well there is ppl with low dps, ppl standing in bad staff and all. then there is wipefest on some bosses. But lets face it, those ppl didn't fine tune their abilities like ppl targetting normal/heroic did. There is some bad ppl that's true, they don't ever want to learn, unfortunately u cant do any thing about them except kick them. other than these, lfr was quite good for me so far.
3) lfr hurting the game: this is most hilarious! it by means hurts ur game, rather it support it more. its keeping casuals by having their share of fun, its helping raiders by quickly gearing up. only ppl i see thinking it hurts r ppl who can't give up memories from past. BC was then it is now. so rather go with what is now.
So overall, from my point of view, LFR should stay and frankly, topics like this shouldn't be up for debate either.