There's already a mod that lets you combine dew collectors into 3X and 9X versions, that can hold 3 stacks of 3/9 jars respectively. Saves on the tedium and the ugliness.Though I agree with you that the daily harvest you need to do to get the most out of the collectors is a drawback to the current solution. I probably will just get myself more dew collectors so I can ignore them for days and immediately collect a bigger stack of water when I need water again. If TFP doesn't do it himself I'm sure there will be a mod to increase the size of the dew collector storage.
Truth be told, I'd love for there to be some long, complicated, automatable process for purifying water. I'd like a long, complicated automatable process for dealing with ore and other things as well (I enjoy setting up complicated factories like Mekanism Ore Processing.) That doesn't seem to be in the cards for 7 Days (even with mods) but I'd love it if the devs added it for water (which would then presumably allow for mods to be made for ore processing and other things.)
In the end, I'm kind of indifferent on the water changes. If filters were much more expensive or rare, I'd definitely dislike them, but as it stands I neither love nor hate them, just think they were kind of pointless.