Gretel Killeen will definitely not be asked back to host next year. It isn't totally her fault, you have to also blame the writers who came up with her material. Most of it was just not funny, including the stuff the award presenters had to read.
That said I think the biggest reason she failed as a host was that she doesn't have the right personality to pull it off. If you don't have the personality to pull in an audience and get them interested or engaged in what you are doing then you will fail. For example, if Rove had done the jokes Gretel there is a higher likelihood that it would get a better reception, a) he is a comedian and therefore he knows how to deliver jokes, read a room and improvise, b) he is a fairly likeable guy, he seems approachable, genuine and pleasant. If you like someone (or at least don't instantly dislike them) you are more willing to listen to them and let them get away with poor jokes.
I don't understand what Nine was thinking when they got her to host it given it is no secret she is fairly disliked by Australian viewers or why they went with just her and not multiple host as they have done in the last few years. So if one fails or isn't doing well you can sub in the other host to save the show/revitalise the room.
In the past the awards have rotated through the networks each year, maybe a station move is what is in order. Maybe Channel Seven or Ten can revitalise Logies night by getting fresh blood (or at least not the same blood) into the production and planning of the entire event. A rotating schedule should in theory push the networks to try to outdo the others when they get their hands on it, so if 9 pulls 1.5 million one year 7 then pushes to get 1.7 or more the next year.
I did enjoy one part of the show, Shaun Micallef's presentation. In my opinion he was the last good lone host of the Logies. Like to see him again, but you have to wonder who would want the job, it's a poison chalice.